The value for trivial may be incorrect.
I've been stalled at 154 for the past 2 stacks.
EDIT:
As soon as I posted this, the RNG gods decided they'd had enough of a laugh, and skill started to climb again.
Stalled again at 167 and 170, though that later feels right for where it should slow down.
Leveling 142-178: results 274 success out of 338 combines (81.07% success, averaging 9.39 combines per level).
If your goal is to level the skill I wouldn't recommend, unless you have melee alts that will use them.
Edited, Feb 15th 2021 5:36pm by Covalerahien