Yeah, I definitely agree with you. Sarcasm loses its punch when it's too obvious.
That said, there are a lot of people on spurstalk who genuinely believe crazy things, like KBP, gui ude27, avante, cosmored, mouse and so many more. Sometimes it's pretty difficult to figure out if a poster is genuinely stupid or stating something ridiculous for the purpose of highlighting its ridiculousness.
I guess when posters use the blue font, even though it isn't really funny, at least you know they don't really believe what they're saying.