Swap Position?

[Martoq]

In combat when in Zone of Control if you have an ally behind you is it possible to swap positions between the Ally in ZOC and the one not? If not, why? It would make tactical sense to move an injured unit off the front line and put the healthier one in its place. I haven't noticed any issue with moving through other units with a different one. Just wondering if I'm missing something obvious?

[Sigismund's Wrath]

Gameplay answer: There are advanced / exalted classes that have that ability, it's limited, and those classes stand out.
Roleplay answer: It does make tactical sense to swap out units, but the enemy isn't just going to let you, so you need units with special training to be able to do that without taking damage.