Hey, all. I'm a relatively new guitar player and I'm trying to learn to play triads (just the majors for now). I've been at it for months and I'm getting discouraged because I don't seem to be making much progress. I have a teacher and he tells me not just to memorize shapes, so every time I try to play a triad I make sure that the notes I'm playing are right (CEG for starters). But it seems that every time I do this I have to recalculate what the notes are.
On the piano I can bang out any inversion of any triad, probably because I've been playing for years. But on the guitar it takes me forever to find the notes. I have the fretboard memorized on at least a superficial level: I can find any note on any string pretty much on the first try, but when I try playing triads everything goes to hell.
I'm wondering if there's some fundamental knowledge that I'm missing, like they're all based off one of the lower strings like a barre chord, or if there's some pattern I'm just missing? It can't be this hard can it?