@Ivotas:
Well I really don't know what might be the case here. However I'd find it a bit weird if the pain comes without damage. I mean even though it was a completely different ability, when Kuma infected Luffy's pain and fatigue on Zoro the body apparently took even more damage (hence all the blood). If it would just be pain and fatigue then Zoro should have been better right now, since pain and fatigue are both temporary things, while damages to the body can become a permanent thing.
As I said, it's a different ability but it can be that this is the Shonen logic of how things work in this world. So I'd guess that for Teach something similar is the case. He's most certainly the tough SOB who'd be able to take it. I'm not saying what you suggest is wrong, but I'd consider it unlikely.
Here a quote
Kuma: What I have just expelled from his body
is his "pain" and "fatigue."
It is all of the damage he accumulated during his fight with Moria and his people.
If you wish to take his place, that means you must accept his suffering.
You are close enough to death already that you cannot survive this added damage.
You will die.
Here "pain" and "fatigue" stand for the damages. So it's not only the pain i was referring back then in BBs case but it's much more as it has been explicitly explained by Kuma.
BB on the other hand mentioned only that his body endures pain as every normal person. It's still confusing cause if the definition of Kuma about pain and fatigue is the same as the one used back then by BB then ok BBs body will also be damaged by the attack.
On the other hand it contradicts the fact that his darkness fruit absorbs the attacks of the opponent. If an attack is absorbed so is the damage this attack would do? Or is the damage partly absorbed? if not why does the darkness fruit sucks the attack if the damages remains? That would be imo pointless.