Outline hurts the worst, because it is so sharp. I would shake on a few lines he did on my shoulder piece where it went over a bone then found the soft spot immediately after the bone (it would dig, no matter how careful you were).

The shading actually wasn't too bad....

UNTIL he started re-shading and re-shading the same area to get the right depth. That's when it started to hurt. Yes there are more needles, but if the artist works on an area numerous times, then it starts to really burn. All you do is grit your teeth and hope that they move onto a new area soon.

So, yes... Coloring doesn't hurt as much if you're not getting too much color done, or areas reworked. But the moment your artist starts playing with 'layers'. Yep. That hurts. Not as sharply as outlines do, but it turns into a nice deep ache.