My theory is that when you get a squib load in a semi-auto, the gun fails to cycle and forces you to at the very least slow down enough to clear the malfunction. If round one of your revolver double-tap is a squib, there's nothing stopping you from giving round two a squeeze.
Therefore, it can be safely said that revolvers are an inherently unsafe design, and should be disposed of immediately, for the safety of you and your loved ones. I am willing to undertake this dangerous task, for a small fee, of course....