My only data point on this is that when I was doing my instrument
training, I flew safety pilot with my CFII's son. He'd done a huge
amount of simulator flying to learn the basics of insturment work, and
I can tell you he was the smoothest insturment flier I've ever seen.
His corrections were almost unnoticable; the plane just stayed where
it was meant to be. I comment on this to his dad later, and we both
wondered if his sim training had giving him this skill...