I find this an interesting photo. Here you can see the fur that is on his lips to hold the food in and his inner lip has such an interesting texture. Also you can see here it looks like he has a split tongue, He would talk if he could. I really don't think anyone did this to see if it would work on a horse. I will assume that it is that way from him folding up his tongue to suck on it like a pacifier. I will get photos of him doing that.
I love horse he is so funny.