The main thing is it isn't weird...it's quite common when you are zapping those kind of resources. The bad thing is if you do have a crash in one w/ the other one going you are taking a bigger chance on corrupting or locking up your software or ruining your other render.There really is no benefit. The pc simply doesn't have enough resources threads or otherwise for there to be a reason to really do it.It doesn't speed anything up.If you could actually queue it up more intelligently it might have some benefit, but they aren't designed that way now.

No need to think outside the box....
    Just make it invisible.