The Triath-A-Lon Debacle

I was reading an interview with Fat Cyclist yeseterday, when I found out something that rocked my world. There's only one "a" in the word "triathlon." There are several reasons why this is so disturbing to me.

1. I have an English degree. Therefore, I take great pride in the fact that I can properly spell, pronounce and punctuate most common English language words. I take so much pride in it that I routinely correct, admonish and chastise people when they don't do this. (In fact, it's part of my job.) I noticeably cringe when I hear W. say "nuculer" (in an effort to say "nuclear") and anytime I see a period outside of the quotation marks.
2. I hate being wrong. I hate it so much that I continue to pronounce the word "mauve" as mohv, which is correct, rather than the way most people say it, which is more like "mawv." I get all kinds of funny looks when I do this, but what's important to me is doing it correctly.
3. I have never in my entire life heard anyone say "triathlon" instead of "triathalon" and I find it mind boggling that everyone in the world I have ever come into contact with (besides Fat Cyclist) says it wrong.

Normally, I wouldn't want to display my ignorance before the world like this, but I just had to write about it because I am honestly floored. Whenever I next use the word, which I probably do once every four years, I'll have to make sure I say it right.