My gelding has been given the all clear but when any one tries to mount on the left he stumbles like he isn't sound. I trained him to allow the mount on the right since I found out but if there a real reason that he can't be mounted on the left?
I'm not a horsey person, but the first thing I wondered was, can he see and hear properly on the left? Wondering if he's a bit startled by the approach. You say he's been given the all clear, presumably you mean a vet has checked him over thoroughly, or did he just have his limbs checked? Have you looked at the saddle to see if that's at fault, maybe causing discomfort on one side? It may be a quirk of his, but I'd be inclined to have a second opinion from another vet.
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