Replying to Will repeated punching of a boot weaken the plastic?

I'm working on getting a pair of XWave 8's to fit my enormously wide and god-awful ugly feet. I'm going to a professional boot fitter, but they're so busy, they're not taking the time to punch out the whole area we agreed to and not even hitting the right area - so next time will be my third time and some may even need to come back in so that the boot isn't too wide by the heel.

For those of you who actually have the background to know this - how many times can a boot be heated and/or punched like that without weakening the plastic?

Now, keeping in mind I'm not a professional boot fitter - one heel was "loose" in my opinion, and the shop guy said it was OK if the heel moved up and down about an inch. Is this bullshit, or are my expectations of almost no heel movement too high?