PS turbulence and laminar flow
for the gap-fillers, but NOT the remaining gaps, to be a risk during re-entry, this is basically the same as saying that protusions on a surface will tend to transform laminar flow into turbulence, whereas indentations on a surface will not really affect the laminar flow (only locally at worst case). If that's so, fine. But do the remaining gaps pose a risk for entry of superheated gas, or does the laminar flow itself transport heat away from the shuttle surface - gaps and all?
That's as far as I can go with this line of reasoning.