I don't think its a bad comparison because of the link you pointed out. I think it is a bad comparison because one is child abuse while the other is not.
That in and of itself is a type of comparison.
Look here's the deal.... the reason comparing homosexuals to pedophiles is a fair, is simple....
Both Homosexuals and Pedophiles are trying to get social and legal acceptance. That comparison alone is what we talk about here in these threads 95% of the time.
For instance.... when a person exclaims...
"Homosexuals are born that way and therefore they should get all the rights that are applied to heterosexuals".
The obvious follow-up question is... Well, if you believe being "born that way" determines the rights you should have what about other types of people who claim they are "born that way"? What about pedophiles? What about serial killers? What about incestuous couples? All of these groups can make the similar claim "I was born with this urge to act the way I do".
Therefore if "born that way" is a determining factor in ones rights then it has to apply to everyone.
That's why it's a perfect comparison.