I never used my thumb on the low E at first, but now I do sometimes as I see lots of videos of Mayer for example and it's influenced me to try it more. However, I can't seem to wrap my hand around the neck with the thumb still on the E and other fingers able to function as normal (reaching for A string w/other fingers always forces my thumb back for example). Is using the thumb important or more a function of one's physical nature or habit? I guess I just want to be sure that if using the thumb regularly doesn't feel right, I don't have to and that's normal.

well some chords unfortunately require you to use it and in some cases its easier to use your thumbs, but yeah i had the same problem but just like anything else practicing and getting used to the idea will make it much easier
actually most teachers recommend that you dont use your thumb, because if you get into the habit of using it regularly then it will limit you in more advanced techniques. At which point you will just have to un-learn and re-learn everything you previously used your thumb for
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The only chords where a thumb might be necessary are inversions, and you can generally find other places on the neck to play them, or a different fingering for the same voicing. For instance everyone plays D/F#, a first inversion 2(thumb)x0232, but you can also play it as a C-shaped barre chord with 254232 not requiring a thumb, think about it...
Okay, that's kinda what I figured. Like I find it useful and comfortable for some stuff like this:

Verse:   S         S
   T          T

But even when something is like 3x-6533 or what have you I tend to play it as a barre chord.
I dont know if this will help you since im probably more a beginner than you but:
try the wind cries mary, somewhere in the intro you use your thumb for the low E and go down the fretboard. It feels funny at first but as you increase speed it becomes normal

Hope it helps, if it doesnt- disregard this message
it's good to use it when you have to, if you watch most rock guitarists, the thumb mutes the low E anyways...and a lot of guys do the thumb wrap, just not suggestd for very fast passages
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Thanks guys, that helps. I will use it for certain chords and when it makes sense and yeah for fast parts I can see I may be better not to use it the way my hand size is.

And voodoochild78 I was just practicing that song, didn't think to use thumb on the starting chords haha thanks!
if you listen to/look at the tab for. the main riff for the mayer song "who did you think i was." it shows that the thumb gives acces to some hammer-on pull off options for riff making on the G string. it opens certian note variations that you wouldnt get playing without the thumb. its a nice option for some songs and just for sonwriting it allows for more diversity
I use my thumb very rarely but you shouldn't get used to it. One time I had gotten used to using my thumb and I was suddently given a classical to play on and I really messed up because the fretboard is so big I could barely reach the low E.
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Indeed, I have developed a good use of thumb on low E for certain parts and it feels very, very comfortable now. It's almost instant instinct when I will barre and when I will use the thumb. Just takes time!
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when im playing hendrix-y stuff i use my thumb, but other than that i don't really use it that much
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when im playing hendrix-y stuff i use my thumb, but other than that i don't really use it that much


alot of styles require you to use it or it just dont sound right, like hendrix.
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