As I understand this Mike it is only required if the related CEL's are generated. No CEL's after my clutch swap out was done aside from an O2 lean/rich CEL that would flag after approx. 2 hours of driving. Was found to be a fitment leak between the cat and midpipe flange which resolved that problem.

Is the CEL masked by chance? Meaning it is produced but does not trigger a CEL warning light?

Sure after an entire engine rebuild or as stated PCM swap this would need to be performed, but a clutch Flywheel swap? Your experience is far advanced just asking to learn. Maybe I need to have this procedure redone to optimize driveability.