scook
You could try setting the keyboard shortcut SHIFT+Z to do nothing in Preferences > Customization > Keyboard Shortcuts Global Area.
I do this on a lot of short cuts. Short cuts are great, for some things, but there's nothing worse than a view being messed up and you don't even know how you've done it.
What I also do is, if I do need a short cut for something, I will use more than one modifier key, or even three, and I've got a gaming keyboard which I've set up so the programmable keys represent a particular key press sequence. The programmable keys are far enough away from my main qwerty keyboard so I no longer have any "accidents."