I know you're supposed to when cleaning, but does anybody do it when they are deadlifting?
Its called hook grip and its mostly a matter of preference (the choice between hook and mix grip)
Do you mean using a hook grip? If so then yes, I actually go all the way and use a mixed hook grip.
I personally don't do it but if you can stand the pain...
It hurts but its very very good. I used to use it but stopped after my thumbs started bothering me