I know my software vendor vehemently defended not showing a range (they show one on non-TRID IO loans) because they are sticklers for following the rule precisely and have a close relationship with the CFPB, it would seem.
I personally think the range is a good thing. I find it hard to imagine that any examiner would take it to the extreme, but you just never know. A very strict reading of the regulation would lead you to believe you have no basis for disclosing it.
Because of construction loans, where the range can be extreme...I ended up putting a NOTICE on my cover letter to explain how the interest payment REALLY works.
But to answer your question on 'is it prohibited', I just really can't say for sure.