What he is saying is the primary source of information doesnt state it has to be used as any sort of action. It does however state that you can use it as a melee attack. Which i dont know how you could read that differently. I see what your saying however, Its a standard action, and you can use that standard action as a melee attack. But i dont think that table limits it to that, i belive the table shows that making a melee attack to sunder during your round would be a standard action, but the text (imho) explicity allows you to use it in other situations, like on an aoo.
And one of the reasons i believe this is - aoo says make a melee attack, sunder says use a melee attack.
The point for me is, i just dont see any rule that specifically would limit you from using that text *which allows you to USE a melee attack* on something that gives you a melee attack.
Edit- And like i said, i realise your saying well it is a standard action because the table says so (but i believe the table - actions in combat - tells you when you take an action to sunder in combat, then it simply counts as a standard action, but i may very well be wrong on that)
And that you have to have a standard action for the text of the special attack to apply.
But i dont buy that. The primary source doesnt explicitly limit to a standard aaction. The table says using it is a standard action. But even still, the rule for the special attack sunder gives it a use that may not be any specific action at all.
