I'm wondering too what his actual issue is? I have a King Jack mounter on the roof, and bought a separate one, as there are times the A/C unit actually blocks the reception if I have to point it in that direction. So I bought a backup antenna that I can mount on a post off the ladder.
When testing the new antenna, I pointed them both in the same direction. The factory roof mount antenna found like 13 channels. Then, I took the new King Jack, and connected directly to the back of the TV and scanned. I got like 32 channels with the direct connection.
So, that tells me, all the coax and connectors Jayco installs, definitely hurts antenna performance.