I'm not arguing against that. Sheesh. I'm saying that we're perfectly capable of hand waving now and then for the rule of cool as long as the concept of the thing in question is clear.

So to clarify;
I am -not- saying a vibroblade would work in real life.
I -am- saying that we don't need to curb the concept of it.

Double clarifying;

If someone says that they have a thing that shoots singing bullets, we don't really need to ask them how the bullets are capable of singing. The point is that they are, and that's all we need to know. If the creator wants to add a sixteen-page technical schematic on how the bullets manage to sing, then go ahead, but it is by no means -required-