In reply to Jon Greengrass:
> Are fingertips pullups any harder than regular ones?
Yes, for most people I think quite a bit harder. Sometimes you get people with very strong fingers who have weak/underdeveloped pulling muscles. Even then you can reduce the edge size or use wrist weights to increase the load on the fingers if needs be. Though for that type of person they're probably better emphasizing the pulling part of the movement anyway since that's their weakness.
I think fingertip pull ups are probably one the most functional movements for climbing. Unlike deadhangs they train finger strength at different elbow joint angles, from fully extended to fully flexed. And of course they train you to pull, not just hang, which is what we do in climbing.
Fingertip pull ups were one of the main exercises used by top climbers in the eighties, before the introduction of home boards and campus boards. And French climber JB Tribout said if someone can do 20/25? pull ups on a 2? cm edge then they had the strength to climb 8b+. Sorry, can't remember the exact figures, but the key point is he thought fingertip pull ups were a vital measure of climbing specific strength.