Size of Y chromosome?

Please check this

http://www.npr.org/templates/story/story.php?story...

http://www.learner.org/channel/courses/biology/tex...

I read that size of Y chromosome has reduced because it did not have partner at all. but X chromosome has not reduced, they say that it is because, it has partner in female sex to recombine.

If Chromosome don't get partner to recombine than there is tendency to delete genes which may be harmful produced by mutation. which intern will reduce the size of chromosome is the logic.

Now if X chromosome gets only 50% chances to recombine then I think size of X chromosome should also reduce to a size in between Y and its initial size in reptiles This is my guess. Please comment.