ok more precise explanation
the gap is the difference between your highest skill mastery level
and your char level
for each point of gap you have you get 10% more skill points up to 190% skill points (9 gap)
You also get less exp for each point of gap you have
So 0 gap fast lvl only 100% skill points
9 gap slow lvl 190% skill points
Oh and you dont have to have a gap to get skill points, but a gap does help you get more skill points. Sometimes you need to get more so you can lvl up certain masteries.
