More of a lesson learnt thread than asking for help.
I?ve been struggling with starting and IAC counts in general with fueling spot on and constant RAF table updates. Russ K idle procedure followed numerous times etc.
The car has a stock throttle body and hole size, wideband, medium sized cam and long tube headers.

It would not start without throttle and then not idle like the fueling was completely off.
UNLESS I used the bidirectional controls to drive the IAC to 0, then off again before starting the engine. It would start, over rev and then pull a heap of idle air out. Throttle blade position, RAF, etc didn?t help. It felt like the IAC did not know where it was unless using the bidirection controls. Manually resetting the IAC (un-plug the IAC, ignition on and off a few times, then plug back in) gave a different result again for the first start (massive over shoot on rpm), then back to being out of whack again.

I was living with the start up dramas and constantly chasing the issue. I got it to a point where it would start and idle ok but run out of IAC counts when 80C\176F. Not ideal, but manageable. RAF table values was stupidly low when warm 2g/s. I chased vacuum leaks etc, but nothing helped. This result made it feel like the total IAC range was miles too small with way too much airflow.

The fix: I pulled the throttle body again and noticed that when the IAC desired and actual were 0, I could see daylight through the plunger opening. This suggested there was extra airflow as the IAC was not closing far enough. I removed the IAC and wound out the plunger to the point where it was fully closed and sealed within the opening when the desired value was 0.
Magically the RAF needed increasing and I now had plenty of IAC head room. Adjusting the RAF table to suit what the car wanted and all is well. The numbers look like they should.

I have no idea how the IAC got messed up. And have no idea why the IAC actual PID was garbage.
The write ups and threads on idle tuning here gave me the confidence to trust the process and look outside of the tune. I hope this helps some poor random dude who ends up chasing this issue in the future.

Cheers