On a 737, are they always on? Because our windows are only on as needed by push button. That's why I say it has not effected our windows like you say it does on the 737, we hit birds all the time in the Summer, with the defog off, that's why I don't see how this gives it flex, especial if it is not on 85% of the time to warm the window up during bird strikes.
Looks like I am not making myself clear, and yes on the 737 and A320 it is on all the time. Below are a couple of sites with window heating/bird strike threads.
And here it start at the beginning7th poster starts the conversation on this subjectI hope this makes what I am trying to say a bit clearer :-/
Matt
I now see what you are saying, I read both forums, and the FAA report in the link. For what every reason I was thinking you meant that the elements gave rubber band like qualities to the window

,not that the heat provided the layers with flexibility. That does make sense.
Now with that I can ask: are military windows made of a higher grade material? since they fly higher then all the planes that every one was bringing up, such as 737's and A320's?
It seems like every one was using those 2 planes as the standard, because this happens alot on those planes. I know the C-141 & C-17 both had off switches, and a sensor to worn aircrew of ice build up. And the C-141 had bleed air for it's anti ice. but the C-5, C-17 & C-141 had crazy angles on there windows, compared to commercial planes, as to deflect stuff maybe.