Tested out for ~30 mins vs boss dummy on geared (~6100 Gear score) warrior, here's some observations.
Uses spell table, so uses spell hit and spell crit.
Can proc a Main-hand Deep Wounds if the proc crits.
Tested over 3 sessison of 6 minutes in length and total damage of the proc was always ~1% of total damage done, not including extra Deep Wounds damage caused by proc crits.
The extra damage from Deep Wounds caused solely by crits from this enchant will overshadow the actual proc damage itself.
If I add the damage I gained from Deep Wounds with the Icebreaker proc, it amounts to ~2.5% total damage done.