EDIT: it just seems like deleting SCREEN can create strange behaviour on the OUTPUT page, like a SPLIT with only one output, an operator without outputs that suddenly has two, etc.
Anyway so far I tried with IS and DIV for instance, adding some SPLIT operators to see if something weird happened again but all seems well. Will let you know if I see something more, just tell me what you need to test and I'll do what I can to help: this feature will definitely make my life simpler in the end!
One thing though: once arbitrary OP deletion is working, will it be complicated to insert operators as well? Not that it is as much needed, but it could help to make some clean programming. Then again, not such a big deal compared to what you are doing right now!