Poor Peanut is covered with pin feathers. I spend some time most nights during Warm Toasties breaking the feather sheaths off, but even though I keep my fingernails long for the job, it still isn't easy. Plus, Peanut only lets me preen the area from the back of his neck to his beak, between his eyes. The sides of his face are a tricky spot. And sometimes he's just not in the mood for any preening at all.
A bird (coincidentally, a parrotlet) at a pet store was in desperate need of preening help, and one of the fellows working there forced the issue. The bird got preened, but she never trusted men after that. Can't say I blame her.