How good was he really? From what I read here and other places it looks like he was controlled by mobsters. He was demolished by some of the best of his era, particularly Louis, Baer and Galento. Was he good skill-wise? Because he sounds like he was a giant sideshow freak who was guided to the heavyweight crown.
From what I understand he didn't have much heart. He had freakish strength and was genetically superior in that sense. However he didn't possess a good chin and he wasnt as polished as shorter guys were. When you're that tall it tends to make you clumsy and no amount of training can make you as agile and as nimble as a guy who is 5-10 to 6 -2. SOme guys come close but you can see that they're very different as a result. Lets's put it this way, you don't see guys who are 6_3 and up doing the peekaboo. This is because they don't have to and wouldnt be able to pull it off the same way a shorter guy can. Someone who is taller has longer arms and you can't be as compact with longer arms. I used to fight very loosely and I mean very loosely out of the peekaboo, but I fine tuned my style to be less of a swarmer as I have a pretty big ape index (i'm 179 Cm tall, but my reach is 193 and a half). Taking into account my reach I realised I can't fight with the same compact style so I adjusted it to be more a boxer/puncher/Slugger than a swarmer, because it would be such a waste to not use my reach.
TL;DR - Long story short Primo mixed it up with guys when he shouldn't have and even though guys like Bowe and Vitaly did mix it up, they have solid chins to back it up with - Primo didn't. Who the fuck keeps their hands at their rib cage instead of in front of their face when facing Louis, arguably the greatest heavyweight of timing, accuracy, speed and power?
I reckon Primo would have been a lot better had he had Emmanuel STeward as his coach. If he had Wlad's approach, maybe he would have matched Wlad's prowess. I guess you could say he's an unrefined Wlad.
Carnera probably didn't have a single fast twitch muscle fiber in his body. He did use his reach and movement very well in deploying his long peskey jab, and he had a number of quality decision wins on his dossier. Against Campolo and Impelletier, he demonstrated that he could handle bigger opponents than himself, and he decisioned the bull-strong Paulino Uzcudun twice. He also posted two decision wins over King Levinski, and avenged a points loss to Jimmy Maloney with one of his own, as well as legitimately outpointing a Tommy Loughran who, while fading at 34, was nonetheless coming off a decision win over the aforementioned Impelletier.
With his jab and movement, he was certainly a better boxer than the equally large Buddy Baer. He may have been slow in the ring, but he wasn't dumb.
He was as well conditioned as necessary for going 15 rounds, and was wearing Loughran down at the end. Stepping on Tommy's feet may not have been clumsiness, but shrewd rule bending on Primo's part. He also pulled Max Baer down with him repeatedly, buying Carnera additional time to recover from his knockdowns. After Sharkey floored Primo with a hook in their first match, Primo immediately bounced right back up, then down to one knee to take the benefit of a full count, demonstrating alert and intelligent ring savy. (Unlike Jerry Quarry, Primo did not lose the count.) As large as Da Preem's feet were, I haven't seen any footage of him tripping or stumbling over them.
Mike Tyson and George Foreman had numerous quick kayos as they originally moved up through the ranks, but Carnera's inability to punch with leverage resulted in him going a significant distance with a number of quality opponents. He had won 13 matches lasting ten rounds or more by the time he won the title with 82 matches under his belt. That's a fairly respectable level of experience, too many fights for Primo to have behind him and still be totally clueless about what to do once the bell rang.
His reputation might be considerably better if he didn't appear to quit against Baer. (If he'd been on his feet by the end of 15 rounds with Maxie, he might have been more respected, as Jimmy Braddock came to be admired for, "going out on his shield," against Louis.)
Was his knockout of Sharkey legitimate? Primo certainly had his moments in their first 15 rounder. When he delivered the uppercut which won the title, Sharkey was in an awkward posistion on the ropes, trying to get away. Primo squared up against him, and pivoted with his right foot directly facing Sharkey, as he drove up with all his bodyweight behind that right uppercut. As slow as Primo was, when I look at his form in that instant, it appears to be a genuinely forceful punch.
During his title run, he defeated top heavyweights in four consecutive matches. It wasn't his fault that Ernie Shaaf chose to get out of his hospital bed ill with influenza to face Carnera in their title eliminator.
In defending the title against Uzcudun and Loughran, he decisioned two contenders who held wins over Max Baer. He may not have been a great fighter, but he was a good champion, the only one to defend the title thrice inside a year's time between Jack Johnson in 1915 (Willard), and Joe Louis in 1938 (Thomas), a span of 23 years. Carnera deserves to be acknowledged as a fighting champion, who didn't sit on the title for three years, and defended it against worthy challengers. And unlike Sharkey, Baer, and Louis, Primo always got up in his biggest fights after being floored.