I can play things by ear on both guitar and piano and there are only two FM songs I can think of off-hand that are in a kind of in-between key, and they are "Murrow" and "Storms." YMLF is definitely just straight-up Gm. However, I've had experiences where I was playing along to an album, and I know my guitar is in tune but it's not sounding right. I think some players are different and change the speed ever so slightly, but enough to change the pitch a little bit. I know that's definitely the case with cassettes (I have a recording of a FM concert from '75 where the whole concert was recorded half a step low, so for example, instead of "Rhiannon" being in Am, it was in Abm), and I've had similar experiences with CDs, especially those that have been played a lot. And you're right, a capo does change the tuning of guitar slightly when you slap it on, but there's an easy way to fix that - just retune after you've put the capo on. I doubt LB would just throw a capo on a guitar and not retune before recording. Also, as an aside, I've noticed that in a lot of FM music books have songs in the wrong key. For example, I have the Anthology of Classics book mentioned earlier, and there are several songs, including "Never Going Back Again" and "Sara," that are off by a half or whole step. Anyway, something to think about...
