Unlock while subtargetting

This is a slightly obscure request, but could we get the ability to unlock from targets while we have a subtarget pulled up? This is a bit hard to explain, so please bare with me.

Often times, I am attempting to tank a set of monsters and one or two will run away from the fray and target a mage. In such an occasion, I would ideally hit provoke and spin my camera around to target the monster in question. The problem is that I usually am already locked on a target and the monster I want to provoke is behind me. I hit provoke and the subtarget reticule pops up and... I can't rotate my camera quickly because I'm locked onto something. If I hit [Numpad *] to unlock target, nothing happens.

This is very aggravating when it happens, and it has on more than one occasion, got people killed.

Before someone says it, yes, this could be fixed by me simply by remembering to unlock target whenever I need to do this. Unfortunately, in the heat of battle, this often slips my mind, especially because FFXI was capable of doing what I am asking for.

If a mod sees this, thinks it is worthy of escalating, but needs me to explain better, please let me know.