Currently, ModelCheck will only find extruded holes that should be regular holes, if the user creates only one hole in the extrude. So the user has a choice..either:
1 - Use a hole feature, which is a little more work, and our current company policy, or..
2 - Use the loophole, (which makes his life even easier) and extrude all holes in one sketch!
If there are more than one hole in one extrude sketch, CYL_CUT_SLOTS will not be flagged in ModelCheck. I believe this doesn't promote proper modeling behavior, rather it promotes the loophole, which is even worse. Please improve the checking process for this.