There have been confirmed reports that the coupler sitting right next to your header is 'glued' in place and that glue melts from the heat of headers and you lose all steering unexpectedly and with no prior warning.
Please if you value your life, take that off and put the stock unit back in there!
Can you provide more info or documentation? I have seen a lot of articles about the Jeep shaft and know they aren't to be used on the later style like 98 up but have seen nothing like you posted. It is a double D so there should be no rotational issues