Well... shooting and jumping are hardly the specialties of X. You should have said he double jumped to avoid Cloud. That's a more feasable way to avoid an opponent, and, since he has the ability, why make use of it?

My argument would begin with the metallic nature of X giving him a certain defense against any attack with a sword. Secondly, I would say that he would at least attempt to use the Zero Saber against Cloud. Cloud would not be able to block it as it is a beam. Aside from that bit of information, the Zero Saber does immense damage to all enemies. I believe it took two hits with the Z-Saber to kill Sigma. (It may have been three, but I'm not sure, although two hits are required for all other bosses - This may vary from game to game. The only game I know of that X uses the Zero Saber is in X-3.)

What is it they say about silence being golden?