The APM you waste on trying to trick out a scan is not worth it. He might as well swap a tech lab and create a Raven to send along his arm, so he no longer needs the scans to move out. Furthermore, he only gets 240 - 270 from a MULE so you might be better of using your Mutalisks to harass unaware SCVs or perhaps pick of a Supply Depot in a corner. Your hidden Banelings on his path will catch another few marines.
Consider how you could spent the same APM on getting ahead in economy and creating a counter against what your opponent is trying to go. You could try to pick his tanks off-guard with Infestors and then roll in with some more Banelings to do a proper Baneling Bust. There are numerous of other possibilities to keep him contained or even get into his base, it all depends on what he produces...
As Sorean mentioned, you could try to work out a strategy. Play a decent amount of games where you try this out and see how you can can reform the game play you describe to be more nasty, combining:
Forcing out stims using your Mutalisks to weaken his Bio Ball.
Hide Banelings in key locations.
Picking of unaware SCVs and Supply Depots.
Take his defense down and roll in with a Baneling Bust.
If your opponent tricks himself into a scanning pattern instead of MULEs, bonus for you!
However, keep you eye out on what he is doing. For example, don't let him counter you with Air...
Be sure to scout the map too, you don't want him to sneak in an expansion.