Both of my regulars (1 male, 1 female & African-American which frequently do have looong nails), have never given me problems. Any discomfort is from them working on a specific area, & I can usually feel the knot they're working - but they also both use their knuckles for deep work.

Ah well - that session was free, and I have another scheduled for Sunday b4 going into guard work. Course, then I won't want to move for my patrol LOL!