This is the most important thing. Anything that helps you hear the music is the right way to learn. In this day of video and online tabs people are forgetting how to listen to music and tend to watch it instead.
The hardest thing I find to teach people is to listen to what they are hearing and transfer it to their fingers. So I think because you used the term “hear what I’m playing” and “Help me hear It” you’re on the right track. To quote the Doobie Brothers “Listen to the music” 
I feel like I’ve plateaued in my playing - more practice improves my technique but doesn’t seem to advance me musically so I’m returning to music theory for a change of perspective and to help me achieve my goal. In time, I’d love to be able to hear a song and be comfortable playing along, improvising a bit as well maybe? Possibly even taking some of the little tunes I hum and turning them into something resembling music but that might be a bit too far!
I took music theory as a kid learning piano. Switched to guitar as I didn’t think piano was cool (should have bought a keyboard!!) The instructors really focused on teaching songs - not even the ones I wanted and I quit. Now 45 years later I’m back. While I’ve had a lot of fun learning to play some songs, I feel that’s only half the journey. I want to understand how/why these songs fit together for my own satisfaction. To me the light went off when Justin introduced the note circle in an early beginner lesson. I then looked at the written materials for modules 1 and 2 of music theory and now I’m hooked on understanding the theory behind the fun. I hope my execution on the fret board can keep up with my theory work!!
Picked up the guitar for first time in my life two years ago at age 47. The joy the guitar has brought me is unimaginable! I just want to soak everything I can to improve my playing … and I’d love to learn to solo over any chord progression right on the spot! Learning about music is a gift and I’m so grateful for all you do to help us learn!
I am a solo player. I would like to play with other people, and to be able to improvise or pick up what they are doing. I am hoping this course will help me get there. I would appreciate any replies, either yes or no. Thanks.
The theory will get you there as in that you’ll understand what is going on, provided that you a) know what key the song is in or b) instantly can recognize chords/notes by ear.
The ability to translate this theoretical knowledge to the physical (i.e. your guitar) is the second part and equally as important.
The main advantage of knowing the theoretical side is that you can “connect the dots” practically everywhere you are at any given moment, without the need of an instrument.
Many “Aha” moments are waiting… 
Hey Gerry - Welcome to the community! Music theory will certainly help when playing with others, understanding the chords in a key or how to play a major scale and so on.
However, I’d strongly suggest that if playing with others is your goal (and personally I think it’s one of the best goals you can have) then don’t wait until you ‘feel ready’, just jump in. Find a local jam group or guitar buddy. However prepared you are, then first time you play / improvise with others is going to be a steep learning curve and the best way to improve is to do it. Start simple and enjoy it, it’s the best thing about playing guitar imho 
All of the above, everything you mentioned - play lead and understanding what I am playing(improvising). Understanding chords and scales and how they relate. I want that aha moment you had transcribing the Metallica song. I may want to write myself one day. I learned playing guitar by ear, lifting the needle on the record and going over and over it until I figured it out. I don’t think I always figured it out correct, but it sounded good and I could play. I have bad habits I want to break and learn the right way, both theory and fingering wise. I never had any introduction to theory. Learned how to read music and play trumpet in grade school, but that knowledge is all gone. I played guitar in a band in high school and kept up with guitar until my early 20’s, then got married, had kids and haven’t picked up a guitar in decades until about 6 months ago when I bought a guitar and some new gear. I remembered how to play the intro to Boston’s more than a feeling! muscle memory or latent recall, who knows, but I can pick and strum like the old days…well almost. I am as old as the guys in Metallica but still have the internal spark I did as a kid.