Making MB pop (and not even pop country, but pop pop) was one of the weirder things that happened this season. If no block she's almost certainly the country singer on Blake's team, and the dynamics of this whole season change.
Katie is Katie regardless of team. If John wasn't willing to advance Mendeleyev to even knockouts, he was never going to be a front-runner on John's team. Something up with that, that had nothing to do with who else was on the team.
Johns's team would have been radically different (and much weaker) without the block though