The case could easily be made that with the heavy explosion and adoption of analytics in baseball, that the days of an MLB manager *needing* to be a tactical genius are pretty much long gone.
Just my opinion, but there's so much useful data out there that quite frankly a spreadsheet/computer program can effectively manage a game from a pure "this is the optimal decision based on the information we have and are using to project the future" standpoint.
Where good managers separate themselves from bad managers IMO is on the interpersonal level. The ability to connect with players. The ability to keep them motivated. The ability to understand that a certain guy needs a kick in the ass where another guy needs an arm around his shoulder.
With that in mind, I very much think being an MLB bullpen coach (and by extension a long-time MLB catcher), is a far better preparation for what it takes to manage at the MLB level than managing in the minors is.
Managing in the minors is fine experience, but it's a completely different animal than managing at the big league level because the overarching goals in each case are often dramatically different.
