Can AR coating be damaged from heating a plastic frame in order to adjust it?

[Arslan]

I brought my plastic frame glasses from eyebuydirect to a store
wanting to get them adjusted. I asked, "Is it possible to adjust
glasses that I didn't buy here." He said that was fine. I handed him
my glasses and when he saw the AR coating he told me it can get
crinkled and ruined from the heat. The heating device they had wasn't
one of those boxes with the beads in it, it was more like a hair
dryer. He said the beads can work okay because the heat stays mostly
on the frame and doesn't get on the lenses, but this device would heat
up everything. He said to confirm first from where I bought them if
heat will damage the coating. I will email eyebuydirect also but I'm
wondering if anyone has any thoughts on this.

[onlineIDoc]

yes, too much heat and some ARs will crackle or craze.

[Arslan]

I got a reply from EBD. They said the coating can withstand heat, but
I didn't ask them whether there is a difference between a using a
hotbox with the beads or using the other device that doesn't have
beads.

I actually got decent results just now using hot water from my
faucet. It comes out really hot here, enough to burn you. I just did
what is shown here: http://www.expertvillage.com/video/40878_adjust-glasses-fullplastic-adjust.htm#postAComment
except I held it for longer amount of time both in the hot water and
while bending it. I bent it enough that the arms almost touched at
the end. It expanded outward again quite a bit but now while fully
cooled it is tighter than when I started so it worked alright.