Carwin's skillset is extremely limited. He relied a lot on people walking right into his 1-2 punch as well as people with defensive woes not being able to defend themselves accordingly.
He was also quite good at bullying his way inside, where his brutal power shone.
I won't dispute that he has a limited skill set – but you
don't need a sophisticated skill set to succeed at heavyweight.
Browne, Barnett, Bigfoot – there are a lot of outlier heavyweights Carwin wouldn't necessarily be the underdog against.
He pretty much only has a 1-2 punch in his arsenal. As soon as he fought someone like JDS who has decent defenses and actual technical ability on the feet, he got absolutely massacred.
More or less true, and the JDS bout was a massacre – but who else could do what JDS that night outside the Top 5?
The best technicians in th division besides the champ are probably Overeem and Arlovski, yet both have been forced to shell up against the cage by lesser strikers.
Now, I would favour Reem over Carwin, sure, but I
could see him breaking that shell if the moment came, and I
do see him eventually corralling Arlovski and putting him away.
(The always-overlooked Werdum might be able to Travis Browne him if he doesn't fight silly, though.)
His wrestling also never came to fruition in the octagon. He was stuffed by Neil Wain who is a nobody, and stuffed by Mir who statistically has some of the worst TDD in HW history. He also got taken down by Gonzaga.
His wrestling was largely defensive, and largely successful in nullifying his opponents' grappling. Did the job.
So you basically have a guy with slow, powerful hands that can't dictate where the fight takes place reliably, who relies on his toughness and one punch combination. He has also lost the standup portion of every single one of his fights outside of the Lesnar fight regardless if he ended up losing or winning.
Can you say this, really? If you're losing the lighter exchanges but still end up knocking your opponent cold in under four minutes almost every time, in what sense have you "lost the standup"?
Then you just couple all of this with the fact that he's 40+ years of age and has to fight under USADA
Not ideal, but the average age the division is 36 and power, Carwin's main tool, is the last thing to go.
USADA regime probably sees him shrink a bit, yes – but everyone's in the same boat, and Carwin is a naturally big man.
This means that, while he may be diminished, it might not matter much if everyone else is diminished, too.
All in all I don't think he'll light the division on fire, but he'll be a welcome addition to the lower half of the Top 10. We need heavyweights of that calibre to match-up with new contenders and guys dropping out of title contention.
A good test for anyone, and if he strung three wins together (conceivable) he might just end up getting a shot.