Flamencology
You don't deserve koa.
Have started doing it lately on one of mine and am loving it.
I did for a while on my '79 The Paul. It's a sound. I used it more for '50's style blues and jazz. I know a lot of the "West Coast" blues guys here in SoCal do it.
Put flats on my 57-RI Strat because I thought it would get me a vintage Buddy Holly kind of tone, but it didn't really, and I hated how dead they sounded. Took them off pretty quickly. I don't recall the brand of strings -- probably Gibson nickel flats. I really should have done more research into what I wanted instead of thinking the strings were some kind of magic ingredient.
On the other hand, I used to have a solid-body 12-string Vox, and Pyramid flatwounds sounded great on it. Kept the same strings on there for years.
Ive only used them on hollowbodies, and bass of course.
But isn't it quite common for Tele slinging jazzers to use flats?