Browsing in google, I came to a forum where someone posted the following: On the bottom it says, Claw: Full claw. What's "claw" referring to?
This is 'the claw', a pretty shoddy picture and with an old 'duke' pad but the basic idea is that you use your index finger to use the X,Y,A&B buttons and your middle finger for the R trigger. The advantage is that you can use melee, jump, switch weapon and equipment without having to move your thumb off of the thumbstick which in turn enables you to continue to look around. I however think bumper jumper removes the need of 'the claw'. You should try it out if you haven't already. Hope this helps.
I never knew that is what it was called. That is what I do, but without even thinking about it really. It just overall helps, I don't see how anyone can not use this setup, it is almost impossible not to.
It all depends on what you're used to. I tried to do claw a while ago for about 2 weeks and just couldn't get the hang of it. To OP: If you're gonna try claw and can't get the hang of it, the Bumper Jumper button layout in Halo 3 is similar.
The bumper jumper button layout as has been said just makes "clawing" pointless it is so much less of a strain on your fingers.