Still have the chance to get run over and landed on by a horse with a pike. Horse can jump you know. Since the claymore is more maneuverable than a pike which would have to be braced into the ground, if the horse jumps you still have the option of hamstringing it, or going for the rider instead. The force of the blow versus the momentum of the horse would easily knock the heavily armored rider off. He wouldn't be able to get up very fast since his armor would be an extra 150-200 pounds, so he'd be easily taken care of.

Though I think we might have to concede that this is a difference of opinion and just simply agree to disagree.

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"BOY: On a hot summer night, would you offer your throat to the wolf with the red roses? GIRL: Will he offer me his mouth? BOY: Yes. GIRL: Will he offer me his teeth? BOY: Yes. GIRL: Will he offer me his jaws? BOY: Yes. GIRL: Will he offer me his hunger? BOY: Yes. GIRL: Again, will he offer me his hunger? BOY: Yes! GIRL: Yes. BOY: On a hot summer night, would you offer your throat to the wolf with the red roses? GIRL: Yes. BOY: I bet you say that to all the boys!" -Meatloaf