Healing Factor does nullify thunderclap. If Hulk can't capitalize, Thing can't capitalize.
Being groggy, weak, and disoriented affects your MOBILITY, which is Wolverine's greatest defense against the heavy hitters.
When has Colossus ever knocked out Wolverine with one hit?
Uncanny # 96: Colossus hits Wolverine with all his strength. Wolverine backflips off a wall and recovers instantly and smiles at Peter.
"The Wolverine just loves to get mad. "
During the 12 story Colossus hits Wolverine as hard as he can in the back of the head. Wolverine gets right back up. This is after Colossus' power-ups.
And anyone who doubts Wolverine could take SEVERAL shots from the Thing needs to look at the above picture of Green Hulk flattening Wolverine with a frikkin Redwood tree. Does nothing but make him angry. Nuke-like impact and it just pisses him off.