As was previously said I always checked the gap and ended up adjusting it one way or the other, usually not much.
I just bought a set of iridium plugs for my ride and found this on the NGK site:
Should I gap my Iridium Plugs?
The manufacturers say NO.
This is because most people do not know how to properly gap a spark plug, and the center electrodes on the ultra-fine iridium can easily snap if mishandled....
.....The manufacturers say an iridium spark plug will run so much better than a traditional plug, even if it is not gapped for that motor,....
So I still checked them and although they were out a few thou. I left them alone. The size of that center electrode is smalll so I figured I'd leave it alone....Mike