Really? I would not have expected a decrease, let alone that large of one. Mostly because I'm a newbie, and wouldn't know. I pulled 280 last night, my 5RM for 3 sets, with a double overhand grip. But I don't think I'll be able to keep doing that. I'm going to start alternating and alternated grip.
I noticed the same thing -- when I got to about 225 I started having issues with double overhand grip. When I got to 255 I started failing sets with double overhand, but the next week I'd get it. At 275 I got stuck for about a month, so I started doing hook grip for my last warmup and my workset. Using hook grip + chalk has elminated grip issues so far -- at least, none on 285 and I don't expect any @ 295. The other nice part is that even though I used to have trouble holding the bar double-overhand for 5 @ 225, I can do 5 @ 225 easy now double overhand. So even though I'm using hook grip + chalk on my work sets, my grip is still getting stronger.
It took me a few weeks to really get the hook grip. At first I was afraid, I think, to really FUCKING SQUEEZE THAT BAR with my poor little thumbs in the way. But I'd rather have sore thumbs then be a pussy.
i'm a pussy about having sore thumbs. mine kill me already so i'm leery of this hook grip.
Hook the grip, Mr Bingley. It's worth it. My pathetic deadlift would be even less impressive without hooking. Plus, the thumb calluses are like no other.
Hmmm, chicks do dig calluses