It doesn't matter if it is three minutes and if all you have to do is dance it away. If it is established that it is a mini-boss or a boss fight with a checkpoint, and there are zero rewards for doing it, mats inclusive, people are bound to skip those illusive three minutes--even if they do it on one toon and save the checkpoint for Crota on the other two. It's three minutes less on something that gives nothing. Repeating that it only takes X amount of time will not change this behavior.