/rest <Can I have it?> <Do you need it?>

[naaros]

But it only works if you have not incurred enmity, so you can't rest up for HP/MP in the middle of a big fight.

It was explained to me that the patch notes said "when incurring enmity" which probably means when casting something. You won't be "incurring enmity" if you are just standing still and not attacking or casting anything.

It also says:

•HP and MP will automatically recover only while the player is stationary, regardless of whether or not he/she is engaged in battle.

Which basically says if you stand still and not cast, you can regen MP while engaged in battle as long as you are not being attacked by the enemy.

That's how I took it, anyways.