I think someone is forgetting how logic pertains to reality. It is logically sound to take up life-tactics and life-strategies that increase the chance that your ends will be met. Distrusting an entity that has harmed people of your group before is a good life-strategy, as anyone knowledgeable in Game Theory will tell you.

I think the example of the lynch in Ramallah was already presented. And the current situation, in which the Palestinians continue to apply violence, when it seems more sensible to stop it, in order to get negotiations started, seems to indicate that it would be a bad idea to apply to them your "common sense."
Even if we do refer to an actual terrorist bombing using an ambulance sent "to the rescue," it depends on their interests. If the leading parties decide that it is in their interest to show their anti-Israeli brethren that they mean business, they may contemplate such acts.

An error on my part. I should have said, "were the Palestinians intent on renewing peace talks and negotiations, assuming that the American intervention is useful for that end."

This would, of course, contradict the reasoning I would have put behind their attempt at sending a car-bomb in the cover of an ambulance.

By the way, I think you have ignored other serious possibilities, for instance, that unbeknownst to the PA leadership, somewhere along the chain of command, a member of a militant faction would decide to use this as an opportunity for havoc, regardless of what the PA leadership would want. Perhaps the Israeli response was also in some way a manner of protecting the PA leadership from its own folly.