An update from me, since this thread has been revived nearly a year later...

My number one impression from working on this for the past year is that after having started guitar as a non-flatpicking '70s-flavor folkie (in the actual '70s) how amazingly hard it is to play less: just BOOM-chuck BOOM-chuck (or comparable in waltz time). Getting the playing sparser (and cleaner, of course). Quitting being so strummy. I think that's the essence of the old-time sound. Certainly for fiddle tune accompaniment at speed, it's essential.

(It's also interesting to consider how diametrically opposed that style is from the contemporary Irish accompaniment, esp. DADGAD, guitar style, which is totally strummy. I have feet in both worlds, as a contra dancer/caller. I also find getting that much strumming up to speed a challenge. ;-)

The other is how ephemeral callouses can be, and how necessary they are. (This being a bad sign of the sporadic nature of my playing.)

Thanks for the link, Angrybean, and for reviving the thread.

~ Becky in Tucson