Patryn, I really just don't understand this at all. What's the point of even saying you're flanking unless you want the +2 bonus?
I think when people ask whether ranged weapons facilitate flanking, they're really asking if they can get the +2 bonus. If your friend opposite is only able to make a ranged attack, then that person is not threatening, and you don't get a +2 bonus if you decide to make a melee attack.
Why would you still want to call it flanking?
Am I completely misreading you? I apologize in advance if I have missed something here.
Edit: Maybe you're thinking about things like using Sneak Attack...
OK, in that case, I can see your reasoning. I suppose that there is nothing in the rules that specifically says a person is only flanking if they qualify for the +2 flanking bonus to melee attacks.
However, I must admit that in my opinion your position is a bit of a stretch. I think you have found a loophole that is correct according to the letter of the law but not its spirit. I think a
plain reading of the Flanking section would be interpreted by the hypothetical
reasonable observer as suggesting that you're only flanking when you qualify for the bonus.
Otherwise, the rule is a little bit silly. How could the defender be so distracted that a rogue can take his or her time to pick out just the right spot to attack, but not so distracted that the same rogue would have an easier time making that very attack?
Oh, and one more thing: If threatening was not a requirement for flanking, why would the rules specifically point out that creatures with 0 reach can't flank? After all, such creatures are perfectly capable of making ranged attacks from from opposing squares--they just can't threaten from opposing squares.