True it states "any action that isn't an ability or spell", but this pretty much limits it to sprint, potions, and weaponskills. None of these will be used between spells, except rare cases where you want to go into melee immediately.

I'd prefer if it was "when you use a weaponskill".

In fact, to be honest, I'd rather sprint were treated like an ability. Including being able to queue the action as an ogcd.