[@Holy Soldier]
I thought that's what his insane enhancements were for. His general physical ability is above the average godslayer (this is in your own words on your CS), most probably outstripping most of the cast (except Aegis, cause she suplexes shit for a living) in physical prowess. It's not far-fetched to say that godslayer would train with other godslayer to gain power, so there are multiple instances for him to retain SOME kind of abilities from them, even if they may be watered. Though, I do understand that there is an apparent time-limit(?) on how long he can keep them. If it's truly that irritating to even adapt an ability, I would say he would be at least C-rank, and not the extreme of D. :/

Edit: On the subject of surviving, he has regeneration does he not? I would not think he needs to take lethal damage to adapt, only be affected.