Does taunt work unless you do some damage?

[Swiggity]

I seem to recall reading somewhere that taunt won't succeed unless you do at least a minimal amount of damage after clicking taunt, or at any rate you generate a minimal amount of hate (i.e., even if you miss your swings). Can anyone confirm this?

In other words, my question is whether merely taunting mobs off casters is possible, or whether you have to swing once or twice as well.