The only reason I've been here since last Thursday is because of how much the letter annoyed me.
I don't have an issue pulling kids out of school for travel, I've done it myself, even when unexcused, and my kids weren't in school the day I saw the letter because they'd both qualified for the national final in their (non school sanctioned) sport.
A grown-up looks at the rules, makes a decision, takes the consequences and ignores the form letter.
It appeared he hadn't bothered to check the rules (though he later admitted he knew before the trip it would be unexcused), and then he blamed others for his choices. Also the "overcoming the tragic loss of a loved one" rubbed me the wrong way - I buried my 11-year-old son, don't think that you are so special that everyone must handle you with kid gloves for just hinting at a death. I also note that he NEVER elaborates on that claim, (like he does on his injury claim) I suspect it was as false as his BQ time. (Also, probably a third of the people who loved the letter had such poor reading comprehension that they think he pulled the kids from school for a funeral, and just happened to run the Boston Marathon while they were away)
"My kids learned more in 5 days in Boston than they do in a year of school" also rubbed me the wrong way - the little special snowflakes would be much better off unschooled than they are in that school you later professed to respect so much, wouldn't they?
Finally, half or more of the letter was all about HIM, not even about the kids. Taken all together, that letter made me think the guy is a giant tool. Finding out later that he knew in advance about the policy, so the form letter wasn't a surprise, and that he never sent the letter to school, only spread it across social media, make me certain that he's an attentionwhore as well as a tool.
Finding out he's a cheating liar also was just the icing on the cake. Seeing his flip flops on the various parts of the story is delightful. ("I didn't post the letter with the intent of going viral!")
It's rare that we get to see the jerks of the world self-destruct from their own actions. That's why we enjoy it so much when we get to see it happen.