I'm going to guess that when you said "It is.", you meant one of three things.It is. Though you don't need to necessarily spam it in a match, everybody who's good knows how to use (that doesn't mean that everybody that uses it is good though...). I never heard of WD'ing being detrimental to one's game once they learn it.
If there's anything I can compare WD to it's like sidestepping or rolling to the competitive scene. And it's not that hard to do either.... I find doing u-tilts harder T.T and they were meant to be in the game...
Edit: This thread is also old, made around the time of E4all.
-"It is a necessary function." It is not. You can play without wavedashing, even against someone who wavedashes, and do just fine. Give it a try sometime.
-"It is an integral part of Smash gameplay." It is not. It's just a convenient series of moves we found and learned to abuse. There is absolutely no reason why it ought to return for the next game. Like I've said before, there are people who are so hung up on this whole issue that they will do whatever it takes to deny that...*drum roll*
WAVEDASHING. IS. GONE.
And it's sad, because like other people have said before, most of the community is basically saying "meh" to this. Okay, so that useful technique is gone; there are still many, many complex facets to each skilled player's playstyle; it's not like the loss of wavedashing breaks the gameplay or destroys the metagame. Those who used to use it will shrug and move on, and those who didn't use it will shrug and move on.
-"It is a must-learn technique." It is not. If it were, it'd be impossible to beat someone who wavedashes, without wavedashing.
It is not necessary or a must-learn technique because if it were then everybody would use it, and those who use it would always beat those who don't. While it is in no way detrimental to one's playstyle, there are some who don't find it as useful for them as others. There are plenty of people, myself included, who don't use wavedashing out of choice. So, what do we do instead?
We play the game. We work around it.
I've beat people who can wavedash (and I mean wavedash effectively) plenty of times. How? By playing the game. By working around it. It's not as hard as you think.
Oh, and just for the sake of bragging, I main Samus and Mario, two of the group of characters that everybody says needs wavedashing to succeed.
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ron561 asked: "What will "pros" do without wavedashing?"
Well, my friend, they're gonna have to do the same thing as the rest of us.
Play the game.
Hopefully, people like the TC will swiftly learn to accept the loss of wavedashing and move on. But if not...there's always Melee. The tourneys will be few, and their attendants will be few, but there's always Melee.