That's the problem though - I don't think that SE had a clear vision for how they expected a taunt to be used. That's evidenced by the fact that it's
a. a skill on only one one tank class, at level 22
b. very strange in the way that it works

Yes, ideally, you want to have abilities queued up to chain along so that you can get aggro back again... But that also begs the question what's the point of provoke? Why not just run up to the mob (which you mostly have to do anyway) and use your chain abilities? Gap closers are essential when parties are spread out, and provoke doesn't function well as such a closer. Tomahawk doesn't generate enough enmity to get the mob's attention unless the player in question stops whatever they are doing, and in the case of healers sometimes that's just not possible. So then your choices are leave the mob there, or take all your other mobs for a ride.

It's not as prevalent as an issue because there isn't much cleaving in this game, but if they ever start designing dungeon content where we have to be a lot more careful about positioning and not running mobs all over the place we'll see more "wtf" posts about how this particular ability functions and why can't we just get a proper taunt.