[Assimilator1]

Haven't see the videos yet, but good write up.
Is their good evidence now that it is dirt that is jamming the injectors up? Last I looked into it, it was just a theory.

Re heat into the fuel pipes/metal filters.
Like you said the fuel filter will feel hotter even where the temp is the same, but don't forget that the higher thermal conductivity of the metal filters means more of the heat will be transferred to the fuel.
Although perhaps the impact is minimal, I think it would be worth insulating the filters to be safe, remember that the incoming fuel will be cooler than the under bonnet air, so temps won't equilibrise, but will stay lower with sufficient insulation.

Btw, any idea what micron size the standard filter is?