"I think it is easy to make notations in the PNR for your current trip, but in the MP account itself is more difficult."

True if you are talking about your future reservations linked to your MP# (but even that can be donealthough it is rare) but not true of the MP Service Center. They create a record of every time you call in and what you asked about or wanted. But I dn't think it would flag you unless they were flagging you for fraud or something, it would just be comments in your record. I think.