True, but is one that never got in the way. That part of the header would get very hot due to the cat located in the first part of the muffler near your ankle.
A slip on or opening up the oem muffler made it a lot cooler.
If anything, it adds a little protection to the sender unit from the header to the ecu.
The very existence of flamethrowers proves that sometime, somewhere, someone said to themselves, “You know, I want to set those people over there on fire, but I’m just not close enough to get the job done.”