There is absolutely no merit in my eyes, from a masculinity standpoint.  There is an argument from a catholic culture/high class perspective, but that has nothing to do with teaching boys how to be men.  The idea that you would preach to boys about masculinity, through fashion, is such a waste of time (and a total contradiction), because men (on the whole) are not fashion oriented.  It would be like attempting to teach girls how to care for infants, by telling them how to sharpen a lawn mower blade.

In your insinuation that those defending the morality of wearing knee-length shorts themselves wear shorts.  Even if they did, it would not matter.  Ad hominem doesn't necessarily mean personal insult, as it is often understood; it just means you're going after the person of your opponent instead of directly confronting the issue.  So, for instance, if a former adulterer were arguing that adultery was sinful, instead of actually rebutting his reasons, you start attacking him for having been an adulterer.  That has no bearing on whether or not his argument is sound.  It's a distraction and a dishonest debating tactic.

1) Well, not once have I ever said that wearing shorts is immoral.

You're missing the point.  You insinuated that those who happened to wear shorts are automatically disqualified from being able to make an argument defending them.  That is a logical fallacy, an ad hominem.

This is the 4th or 5th time in recent weeks that people have tried this tactic.

If you defend something as licit, it must be because you yourself engage in the practice.  It's equally possible that one has sincerely determined the morality of a particular activity before engaging in it.

Every one of these points is either an outright lie or a gross distortion based on your having not qualified what I wrote with the appropriate distinction.

More slander from SeanJohnson.