I've searched for debates on this topic but I can't find one really... I was looking for pro's / con's for this.
When I was doing skull crushers I had a gym trainer come up to me and say "Try using a thumbless grip." I told him "No. That's not really safe" and he just looked at me weird and said "Ok" and walked off.
Now, my girlfriend and my sister are both personal trainers as well. Both of them were also very much into gymnastics when they were younger. If you ask them, they always used the thumbless grip when doing gymnastics for a basic reason: It allowed ease of release. Meaning, when they were working the parallel bars and such and they had to have a quick release, their thumb wasn't in the way. The thumbless grip leads to less of a grip and ease of release. On the other side, wrapping your thumb around the bar increases the grip. If someone in gymnastics were to use their thumb while gripping a bar, their grip would increase but that defeats the purpose when doing the activities they do. They need a loose grip on parellel bars so they can release it quickly and also spin and swing around the bars properly. The thumb would get in the way of that (and possibly jam or break in the process).
Now, bringing that to weight lifting. Why on earth would you want a quick release of the barbell?! Don't you want a tight grip? I understand using a thumbless grip helps take some stress off of the wrist, but why should you sacrafice your safety? Simply focus on keeping your wrists straight! That's what I've always done, anyway, and I've never experienced any added stress on my wrists as long as I keep them straight.
Was this already debated? I couldn't find it... If not, what do other people think of this?