I use tone knobs quite a bit. How much effect they have depends on the particular pots and electronics used in a given guitar (and maybe some influence from the rest of the signal chain, too). Even on less expensive guitars where they might’ve cut some corners on the electronic components there’s usually some effect.
I had a little play with mine this week ( having said I noticed little difference ). On Pacifica 112v it tends to go from clean relative bright to pretty muddy ( unusable really ). On PRS SE it definitely works much better especially if you just roll it off a little… it takes it from bright to something more mellow. All the way down and the tone loses definition but still usable. I have not tried my HB tele yet but I expect to be in the Pacifica category.
The tone definitely doesn’t go clean bright to gnarly though ( which I would perceive as more distorted).
I’m still not convinced it’s a major component for me in shaping tone but perhaps to even things out between patches in my PodGo it might be useful. The challenge will be remembering to use it.
I agree with @J.W.C. My tone knob does a lot. Almost always fiddle with it, seldom have it all the way at 10, even if it’s only rolled off a little bit. And that’s on a cheap guitar - Squier Affinity. Sounds like something is broken.
All tone knobs present and fully functional on my Hagstrom Viking (separate vol/tone for each HB)
and Fusion III.
Turning down tone sounds as if I am progressively draping thicker cloth over the loudspeaker.
I don’t think I have ever played them except on full, same as the volume knobs.
I had forgotten that I can pull the Fusion III tone knob to split the HB to a single coil, which also alters the tone significantly.
I have made an inventory of all weapons in my armoury, for the day I embark on the inevitable tone quest