ToME: the Tales of Maj'Eyal

In my latest game (arcane blade) I used the crystal focus and heart to make a voratun crystal waraxe and crystal armor. The set gives "Talent on hit(spell): Manathrust (10% chance spell level 3)" on the axe. However, it actually procs 100% of the time, even when I'm wearing my offset. This is very nice for my arcane blade, but seems a bit off

edit: it actually seems to go off multiple times, and only on single-target spells (ie, not flameshock)