Mitigating over-analyzing players

[tarsusc81]

In the group I play in (where I'm always the Zombie player), the general dynamic tends to be that a couple of Hero players meticulously analyze and plan out every detail of the Heroes' overall strategy and each Hero's individual turn. This has two main negative effects:

#1: The game takes forever. For example, we played a game of Supply Run this weekend, which has 17 turns allocated. They won by turn 9-10, and by that time more than 2 hours had passed already. Games where we make it to the end of the allocated turns take longer.

#2: Things become very boring for the other Hero players who aren't as strategy-minded, or just not inclined to try and speak up in the discussion. They end up spending a great deal of the game waiting while others talk, and on their turns they simply do what they're told.

Has anyone else run into this problem? Any ideas on how to counter it?

I'm not sure how you would place/enforce any kind of limit on how much collaboration there can be between Hero players. I suppose placing a time limit on each Hero's turn would help. The problem common to both those solutions, however, is that, despite all their collaboration, my Heroes often lose in scenarios other than "Die Zombies Die." Having less time/opportunity to strategize might just frustrate them.

An option, at least for game length, would be to try and adjust the turn limit and objectives to make for a shorter game. (That wouldn't do anything about engaging the more passive players, though.) Has anyone tried this? I anticipate it might be difficult to balance. Simply reducing the turns and objectives by equal measure might work for some scenarios, but in others the first few objectives are easier to achieve than the last ones.