This exact process of converting triads to 3rds labelled as partial chords, by removing a note on just one string for each, can be done once again for the sets of 3rds on the D & G strings, using E-shape triads.
Here are those triads as seen earlier.
Once again, by always removing the fifth from each triad which this time is always found on the B string, we will move to 3rd shapes.
1] E minor triad → 3rd … … … … … … … … 2] F# minor triad → 3rd
3] G Major triad → 3rd … … … … … … … … 4] A Major triad → 3rd
5] B minor triad → 3rd … … … … … … … … 6] C# diminished triad → 3rd
7] D Major triad → 3rd … … … … … … … … 8] E minor triad → 3rd
So, so familiar. 
The original TAB of 3rds could be labelled:
Where the chord names are really partial chords, intervals between first and third, where the sound of the 3rd is suggestive of the chord.
Putting all three sets of TABs together, with each 3rd labelled as a partial chord, we have:
B and E strings:
G and B strings:
D and G strings:
More on this concept of 3rds as partial chords to follow in part D.
Cheers 
Richard
Questions / comments?
OMG my brain hurts, this is really good stuff to learn about!
Crystal clear… 
Hi Richard,
Am enjoying doing this with my guitar,
Quick Q about the C# diminished E shaped triads here .
It looks like got a perfect fifth - second string 9th fret instead of the flat fifth.
Is that just a typo?
Phew,
I’m glad it’s the simple explanation.
And not an harmonic existential crisis
A couple of paracetamol should see you back in the game Darrell! Glad you’re enjoying it.
Like mountain-streams! Thanks Roger.
Nobody needs that sort of thing in their life! haha
3rds & Thirds Part D : The Ambiguous Nature of 3rds as Partial Chords
Each of these 3rds, as tabbed at the very start of this topic, can be suggestive of the chord from whose CAGED shape it derives. They can be thought of, and heard as, a partial chord, a chord fragment.
BUT … BUT … BUT …
Two notes does not make a single, unambiguous chord.
Let us look again at the pairs of notes contained within each 3rd. For consistency, let us start with the 3rds on the B & E strings.
Here is each, this time labelled only with the note names and the character of the third they contain (Major or minor).
Look carefully at these and now recall how the chords from the harmonised D Major scale were built using stacked thirds. Each ascending note was a third above the previous note. Each Major chord comprised a Major third followed by a minor third. Each minor chord comprised a minor third followed by a Major third. Might it be possible that these pairs of notes, these 3rds, can be seen as belonging to more than one chord?
Bingo!
Darn right they can.
We shall see each of the 3rds and set them alongside the various chord formulae next.
Ambiguous 3rds
Starting with the 3rds on the B and E strings.
1]
C# diminished chord = C# - E - G
A Major chord = A - C# - E
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a C# diminished chord or the 3 - 5 of an A Major chord.
It is ambiguous.
2]
D Major chord = D - F# - A
B minor chord = B - D - F#
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a D Major chord or the 3 - 5 of a B minor chord.
It is ambiguous.
3]
E minor chord = E - G - B
C# diminished chord = C# - E - G
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of an E minor chord or the 3 - 5 of a C# diminished chord.
It is ambiguous.
4]
F# minor chord = F# - A - C#
D Major chord = D - F# - A
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of an F# minor chord or the 3 - 5 of a D Major chord.
It is ambiguous.
5]
G Major chord = G - B - D
E minor chord = E - G - B
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a G Major chord or the 3 - 5 of an E minor chord.
It is ambiguous.
6]
A Major chord = A - C# - E
F# minor chord = F# - A - C#
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of an A Major chord or the 3 - 5 of an F# minor chord .
It is ambiguous.
7]
B minor chord = B - D - F#
G Major chord = G - B - D
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - b3 of a B minor chord or the 3 - 5 of a G Major chord.
It is ambiguous.
8]
C# diminished chord = C# - E - G
A Major chord = A - C# - E
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a C# diminished chord or the 3 - 5 of an A Major chord. Already seen an octave lower.
It is ambiguous.
9]
D Major chord = D - F# - A
B minor chord = B - D - F#
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a D Major chord or the 3 - 5 of a B minor chord. Already seen an octave lower.
It is ambiguous.
The original TAB of 3rds could now be labelled with two chord names for each 3rd:
Where the chord names are really partial chords, either the Root and 3 of the chords named along the bottom row or the 3 and 5 of the chords named along the top row.
Whoa.
Hold on there.
What is happening here?
A small recap.
The seven chords of the harmonised D Major scale are:
D - Em - F#m - G - A - Bm - C# dim
If any two notes of any of these seven chords are sounded, then you can hear them as partial chords, chord fragments, suggestions of that chord. This sense will be further affected by any bass note that is playing (maybe on a drone string) or full chord in a backing track.
We arrived at an understanding of the shape, the derivations and a possible way of defining the chords by thinking of the harmonised chords as CAGED shapes, stripping those back to triads then removing one further note to arrive at simple pairs. And we came right back to the start - thinking that each 3rd represented one chord from the key of D Major.
Look again at the newly labelled TAB.
Each 3rd can be seen / heard as any one of two of the seven harmonised chords.
Ambiguous 3rds continued …
Let us now go through an entirely similar process for the 3rds on the G & B strings. Here is each, this time labelled only with the note names and the character of the third they contain (Major or minor).
1]
G Major chord = G - B - D
E minor chord = E - G - B
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a G Major chord or the 3 - 5 of an E minor chord.
It is ambiguous.
2]
A Major chord = A - C# - E
F# minor chord = F# - A - C#
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of an A Major chord or the 3 - 5 of an F# minor chord.
It is ambiguous.
3]
B minor chord = B - D - F#
G Major chord = G - B - D
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a B minor chord or the 3 - 5 of a G Major chord.
It is ambiguous.
4]
C# diminished chord = C# - E - G
A Major chord = A - C# - E
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a C# diminished chord or the 3 - 5 of an A Major chord.
It is ambiguous.
5]
D Major chord = D - F# - A
B minor chord = B - D - F#
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a D Major chord or the 3 - 5 of a B minor chord.
It is ambiguous.
6]
E minor chord = E - G - B
C# diminished chord = C# - E - G
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of an E minor chord or the 3 - 5 of a C# diminished chord.
It is ambiguous.
7]
F# minor chord = F# - A - C#
D Major chord = D - F# - A
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of an F# minor chord or the 3 - 5 of a D Major chord.
It is ambiguous.
8]
G Major chord = G - B - D
E minor chord = E - G - B
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a G Major chord or the 3 - 5 of an E minor chord or. Already seen an octave lower.
It is ambiguous.
9]
A Major chord = A - C# - E
F# minor chord = F# - A - C#
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of an A Major chord or the 3 - 5 of an F# minor chord. Already seen an octave lower.
It is ambiguous.
Maybe we can already anticipate what will follow …
The original TAB of 3rds could now be labelled with two chord names for each 3rd:
Where the chord names are really partial chords, either the Root and 3 of the chords named along the bottom row or the 3 and 5 of the chords named along the top row.
Maybe we can already anticipate what will follow …
Ambiguous 3rds continued further still …
Let us now go through an entirely similar process for the 3rds on the D & G strings. Here is each, this time labelled only with the note names and the character of the third they contain (Major or minor).
1]
E minor chord = E - G - B
C# diminished chord = C# - E - G
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - b3 of an E minor chord or the b3 - b5 of a C# diminished chord.
It is ambiguous.
2]
F# minor chord = F# - A - C#
D Major chord = D - F# - A
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - b3 of an F# minor chord or the 3 - 5 of a D Major chord.
It is ambiguous.
3]
G Major chord = G - B - D
E minor chord = E - G - B
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of a G Major chord or the b3 - 5 of an E minor chord.
It is ambiguous.
4]
A Major chord = A - C# - E
F# minor chord = F# - A - C#
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - 3 of an A Major chord or the b3 - 5 of an F# minor chord.
It is ambiguous.
5]
B minor chord = B - D - F#
G Major chord = G - B - D
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - b3 of a B minor chord or the 3 - 5 of a G Major chord.
It is ambiguous.
6]
C# diminished chord = C# - E - G
A Major chord = A - C# - E
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - b3 of a C# diminished chord or the 3 - 5 of an A Major chord.
It is ambiguous.
7]
D Major chord = D - F# - A
B minor chord = B - D - F#
This 3rd could be seen / heard in one of two ways.
The two notes could be the 3 - 5 of a D Major chord or the Root - b3 of a B minor chord.
It is ambiguous.
8]
E minor chord = E - G - B
C# diminished chord = C# - E - G
This 3rd could be seen / heard in one of two ways.
The two notes could be the Root - b3 of an E minor chord or the b3 - b5 of a C# diminished chord. Already seen an octave lower.
It is ambiguous.
