Truthbearer’s Chance-on-Hit currently only benefits tank and DPS Paladins. The corresponding Druid weapon has a chance-on-heal effect for resto and a chance-on-spell-damage effect for boomkin, and the feral version has a chance-on-hit for their melees. There’s a special proc for every spec on there.
But Truthbearer has no chance-on-heal effect for Holy Paladins, the cool proc does nothing for us. I think it would be simple to add a chance-on-heal effect so the epic class weapon isn’t just a glorified stat stick and has some interesting proc on it.