I thought Mike's play at tribal council was outstanding. Threatening to give the idol to Shirin casts doubt within the alliance. But the real genius of it was saying one vote was going to Tyler while the other would go somewhere else. If he had simply said "The two of us are voting for Tyler; you should too" then there's a good chance the strong six (aside from Tyler) would think "Well, let's just stick to the plan of voting Shirin. If she does play an idol, I'll still be safe and Tyler will go, which wouldn't be all bad. If he's bluffing, then Shirin's still gone."
Even though his bluff didn't work, it still accomplished two things: he got to keep his idol which he'll surely need, and, as he said, it caused two people to switch votes, which should cause some conflict and work to his advantage.
Also, why Will voted for Dan, I don't know. Maybe there was a reason that was edited out, but most likely he's just dumb. Tyler and Shirin should be the only votes he should consider if he's looking to increase his odds of staying.