Check the original thread (search WAC it'll come up) or read through the advanced olimar discussion section to find out the community's current understanding of the move Ykoahi =) It isn't an unstoppable power of Olimar's though, first many characters have such moves. It still gives Olimar the damage as well, so it requires a certain hesitance and play style developed around using it in order to reach even near 300%, and such a play style is so defensive that in a competative game one would rarely ever damage their opponent, making it a losing strategy. However to prevent a singular bad situation where dodge/shield would not is useful, learn the technique, simply don't go looking for 180%+ lives.
@Fredd I don't believe there really is much of a counter strategy, not one that needs much thought I suppose. The only counter is Grabing or long multi hit attacks. If you can be grabbed you should be shielding not WACing. Long multi hit moves are a "counter" to WAC, however the adjustment for olimars against such a situation is go back to normal survival, and when you avoid the long move you'll have time to hit them. Like i said though, I don't think any opponent would or should make an adjustment for this tactic. 95% of situations something other than a WAC is more useful, you won't take the damage, so if the olimar is soaking up that damage with WAC, no loss for the opponent, they normally would not have even hit there.
-True