Brawling with Kaido without Haki and running down the time limit wouldn't be a bad thing, it would actually be incredibly hype, but I don't think that's what is happening.
Not damaging Kaido with haki is fine, he is a stamina freak, it's not like anyone else on the roof is doing any damage to Kaido, at least Luffy isn't giving up.
Not damaging Kaido with haki is fine, he is a stamina freak, it's not like anyone else on the roof is doing any damage to Kaido, at least Luffy isn't giving up.