The thing is, when the team ask "is this really the simplest way...?" what they're really saying is "we're not convinced, can we talk about this?" They're trying to open a dialogue. Replying with a stock, amorphous phrase like "kill several birds with one stone" is a conversation stopper.
It's not about whether the idea is really a good or bad idea. It's that the team feel that the proposed course of action doesn't make sense, or that a better one is apparent, but that the leader ignores their concerns. That's going to destroy morale. If, as the leader, you can't even convince your own team that your idea is good, it's probably not good.