now apply an edit mesh modifier again to select the separate cut element, for further animation using the X-form modifier. see the image
this way u can get a completely textured cutting animation..
CONCLUSION:
though this was a basic idea for creating such cutting animations using BOOLEANS , though u can experiment on your own with combination of boolean and some modifiers to create for awesome dynamic effects.. though BOOLEAN has some problems, like is alters the mesh topology, still it can produce some decent effects and u can play a bit with it to get the effect u want.