Apex of Thought status effect conversion is very inconsistent

The effect “While standing on your Glyph of Dominion, 100 % of your (ignite/chill/shock) chance is converted to (fire/cold/lightning) resistance shred chance.” seems to work very inconsistently, at least for chill > cold resistance shred.

At first it didn’t seem to work at all; no resistance shred was applied, and chill was.
After trying in a few monoliths, sometimes resistance shred was applied, but more often than not the conversion didn’t work (if I had to make a guess, at most 30% of the time it worked).

I have checked my stats, and have 93% chance to chill attackers (not skill specific).
I’ve also tried with both Frost Wall and Frost Claw, and haven’t seen a significant difference of the conversion happening between the skills.

Hope this info helps.
PS: still very much enjoying my frostbite runemaster build though.