People ask 'did you see the Bisping fight?' as though it means something. This isn't some universe where Sonnen never fought Silva, and didn't take him down multiple times for five rounds straight. The fact is, one doesn't need to see the Bisping fight. We've seen Sonnen vs. Silva, and we KNOW that the former can take the latter down almost at will. The proof is in the pudding. The tape exists.
Had these two men never fought, and we were looking to where Sonnen might struggle, sure... not being able to take Mike down and keep him there might come into debate. But again, Sonnen vs. Silva happened. And Sonnen took Silva down repeatedly. There's really no disputing that. He's shown that he can take Silva down easily. And he's likely to do so again (though whether he gets subbed is a different story). If Sonnen wants this fight on the ground, their first fight dictates it's likely to go there. These are facts. Facts based on empirical evidence. Empirical evidence from a fight that happened and can't simply be ignored because we feel like it.
Finally, Bisping isn't Silva, and Silva isn't Bisping. What happened with Mike is irrelevant. All I took from that fight is that Bisping has far better TDD than Anderson Silva.