Yeah, in addition to the post
@g*r*b is referencing, Schaub has talked about this from when he trained with Stipe. Basically he said that Stipe's offensive BJJ in terms of his submission game is fairly limited and you won't really see him fishing for different types of stuff while rolling... but he is insanely physically strong and has a really solid "base" along with a good sense of awareness/defense that makes him nigh-impossible to manipulate, sweep, submit, etc.
Normally I wouldn't really give much credence to Brendan's thoughts on anything in the fight game, but since these are his personal anecdotes from the training room that gel with other things I've heard & seen I'm more keen to believe them. For instance, Stipe actually competed in a BJJ match years ago for charity. The guy he was up against was more experienced in sport BJJ and beat Stipe... but not in the way you might think. Miocic actually took him down and held him down with ease the entire time, but didn't really know what to do after that, lol. It was Stipe's first wearing the gi, so he just relied on his wrestler instincts and pancaked the guy flat for minutes at a time. Meanwhile, his opponent desperately threw up multiple submission and sweep attempts from bottom. Even though Stipe easily shut down all of them, this ruleset dictated that the more "aggressive" grappler would win if the match went the distance.
I think it's also worth remembering how he survived the Overeem guillotine. He probably came into that fight expecting a striking match, i.e. hadn't drilled a ton of sub defense. Yet after getting badly rocked and dropped, he was still able to regain his composure and survive a tight guillotine from Alistair. Bear in mind, Overeem has won 8 (?) pro MMA fights by guillotine. Hell, he dominated the ADCC European Trials and won a gold medal back in the day by tapping every single guy in his weight class... all by guillotine. Overeem has also supposedly out-grappled Werdum and Oleinik in the training room (source: Oleinik himself). Stipe surviving Alistair's signature choke
while hurt and coming back to win the fight is no mean feat.
I do still nominally favor Jones because I'm worried about Stipe's age, wear & tear, and inactivity... but Jones also has some red flags surrounding him that Stipe could potentially exploit if he comes correct, I'll admit.