My monk has enervation and it works good giving weakened status to enemies he crits.  I was curious if rooting pain could deliver a crit and thereby deliver enervation.  That would be a good set up because rooting pain fires a fair amount I have noticed on another monk playthrough.  On that playthough I didn't think to test rooting pain crits and I didn't have enervation.

Afaik Enervating Blows only works with melee weapon attacks. I did the Witch Doctor build in this forum which uses the Long Pain (ranged fists) and even those don't trigger it (because non-melee). Rooting Pain is an AoE attack that neither counts as melee nor as weapon attack. But it can trigger Resonant Touch charges if it does enough dmg (e.g with a crit vs. low crush DR).