So I applied some extra heat shielding to the inside of my heat shields tonight and ran it for about 10 minutes to heat up and I'm kinda thinking that it did more harm than good.
I'm using but I think due to the thickness of it, it's making direct contact with the pipe then touching the heat shield, helping heat to transfer into the shield better than ever which is the opposite of the desired effect.
I don't have a temp gun to test it with to be for sure, but that's my initial impression from actually doing it and having my leg next to it.