Shoulder Tackle's stun really is situational to begin with. You'd need to be in a situation where nobody can stun something that's being cast and you're 10 yalms away for some reason, which is pretty ridiculous. I guess it's decent for approaching mobs in the open world, starting with a stun to get off a positional, but other than that... really kinda useless. To be fair, though, there aren't many bosses at end game that need to be stunned, so it's not the biggest issue but I don't think anyone would complain if they took away the stun.