Seriously, it is just not a good idea to respond to a letter of rejection with comments like this:
"I cannot imagine what would have caused you not to interview me. Did you even bother to speak with my past employers about my qualifications? I find it hard to accept that you have no place for a person with my abilities and skills."
Huh. In an entire world filled with smart, well-qualified people, you can't fathom that some of them might have been a stronger match than you?