@phantomrant: How can one be sure that it will in fact be effective against Godara ? & Once again how can one be certain that Guy's use of the same technique be greater than Dai's ?
Standard logic and intuition...?
Kishi literally gave Gai his BACKSTORY right before awakening the Eight Gates, something that would kill him. Eight Gates Formation already received a lot of hype. There's a reason why he's having Gai taking on Juudara alone, with nothing but mere Taijutsu. You don't think that Kishi won't shit on Gai's character and actually make Night Elephant deal at the very least significant damage to Juudara, when it was stated a chapter earlier that Senjutsu and Taijutsu are the only things effective against him. ALMIGHTY ~ DO me a favor --> Believe.
Juudara was unable to react to Eight Gates Gai's speed until he stopped right in front of him, and this is after Juudara was fully cautious of the Eight Gates Formation and had Gai in plain view, not to mention the distance between them. And the fact that in his battle against the Bijuu, Gai stated that he would have to use the Eight Gates to counter 5 Bijuudamas coming at him at point-blank.
You think Dai who couldn't even take out a single Swordsmen.....would be able to replicate these top tier feats? If Dai's Gates were indeed on the same level as Gai's, he would have effortlessly speedblitzed every single one of the Swordsmen and would have likely one-shotted every single one of them.