Why are you arguing about a move that has never been used usefully in tournament? Seriously. It's worthless...
Why would any of you want to argue over dins fire? It's a horrible move...
Sure, you can edgeguard with it in some cases, but don't all of you know how slow zelda is? Usually you hit people off the stage from the center, more often the the edge with her fair or bair. In this case, you have to run all the way over to edge, then use dins fire, and by that time they will already be in a position to recover past it easily.
Also, you cannot follow up your moves with dins fire because it makes zelda stationary. Why would you want to get in a few % over position on your opponent? Zelda is slow, and doesn't get the chance to gain position on her opponents often, and using dins fire instead of spacing yourself to punish your opponent just doesn't make any sense.
You can argue with me, and say that you can do a certain thing, at a certain %, but it doesn't matter. Over a whole match or set, din's fire will never change the outcome of the match. You never get enough chances to use it, when there is something better to do. Sometimes its just better to position yourself rather then attack as well.
Basically, any zelda player could NOT use this move and do just as well or better then if they DID use it. And even if they did use it and did just as well, so what? That doesn't make it any better of a move.