Bet you never thought about the actual conduit fill ratio underneath those tight bends. Frank was right about the radius, but here's the thing nobody talks about: even with a perfect 90, if your wire fill is over 40 percent, that tight bend turns into a friction nightmare anyway. I measure my fill first now and adjust my bender to match the load, not just the code minimum. That old timer probably saved you from a headache down the line, bet he had a reason for everything he did.

Ran into a friend who works at a bodyshop and he said they've seen it mostly on the white and silver Fords from the last couple years. He mentioned it's almost like the clear doesn't bond right on certain panels.

Pre-filter is the real hero, main filter is just backup.