re: weak response - not really
There is an indication of poor manufacturing of the TEGA doors. Other than that, I suspect your armchair solution may have problems much like the Teflon idea, especially the idea that you can skip having a screen on the over doors.
If you really want to draw conclusions, though, you should examine the design and testing protocols for Phoenix.
Saying "I wonder if they shoulda done this" is very different from accusing the project of mismanagement and bad design. I'd stick to the former.