Here are my comments:

It's true that the audience is looking for entertainment, but that's most of the audience. The hard-core strategists are probably looking for credibility as well. And I think both Coach & Sophie are credible there. Coach is just larger-than-life and more entertaining.

Cochran would have lost if he'd remained with Savaii anyway. Although it's unlikely he would've gone in twelfth, there was still a chance that he would have done so. But if most of the "cool kids" had realized how insecure Cochran felt, they might have reassured him the way Coach reassured the outliers on Upolu, and Cochran might have felt more comfortable in taking the risk of the purple rock.

Although it's theoretically possible that Ozzy can win, I really doubt it and I think it's more likely that Coach will win (at least when compared to Ozzy). The editing is partly responsible for this, but so are Ozzy and Coach's own actions towards the outliers on their tribe (for the most part), as well as the actions of each guy's tribemates. Albert & Sophie may have wanted to keep Mikayla, but it was probably because they saw Mikayla as a back-up plan for them -- and they lost anyway. Jim, Cochran and Dawn wanted to get rid of Elyse in order to weaken Ozzy -- and they won. So Coach had more success pre-merge than Ozzy and of course, he had much more success post-merge than Ozzy.