I am assuming they need luclin models to be on? Out of curiosity. I like the Luclin models, just kind of oscillating between them and the classic ones. They both have their merits.
Luclin models must be on to mount the horse and use its movement rate. While mounted, the character is always meditating when not moving or when not casting. (Also melee??) If you turn all "new" models off you will be able to summon the horse buff icon and meditate while standing. The movement and casting restrictions still apply and you get no movement rate changes from the horse buff.
Awesome, that is exactly what I wanted to know! Very cool, that is how I remembered it on live as well during pop. +1 for the detailed explanation.
To do that, you need this setting in the ini: AllLuclinPcModelsOff=TRUE - This disables Luclin models. This also allows use of the famous horse bug that existed on AK where you don't have the limitations of horse speed up/down that you do with Luclin models on.