Heraldric horses were originally "shot down" as an idea due to the heraldry being static (No flapping in the breeze).
However, I still do not care, and would love to see them anyways. We already have a horse that has chain down to the ankles, and it looks fine despite being static, so why not Heraldry.
This would also significantly spice up cavalry, and really make clans shine. Oh, and cut down on people accidently killing teammate horses due to it being slightly more obvious due to the heraldry.