I have grown my nails on my right hand, but ONLY because I play classical as well as blues, etc. If I weren't studing classical, I'd probably cut them off. Steel strings aren't very healthy on nails. If you don't play classical, I'd recomend to stick with finger tips.

2) I've always been one who used 3 fingers (thumb, index and ring) and a fourth when I need it. As for your friends assignment, I was advised to do that with the "Oh Papa" rag, and haven't gone back since. I don't see a benefit. Holding to that assignment doesn't work in classical, doesn't work in any of the blues I play(or at least would make it harder!), makes travis picking harder than it needs to be (at least in my oppinion). I don't see an advantage to that assignment. I'd forget about it if it doesn't feel natural.

As Stefan Grossman likes to say, "No Rules!"

Benjamin