That was funny and unexpected. But I think it's one of worst ways to end a fight with a crazy strong dude like Cracker. I think the intensity of the battle should've been a bit higher. It may sound and look logical and all but the fight seemed more like a comic relief than a serious life threatening battle in a Yonko territory. It's sad, but for me, the tension and the Yonko like vibe have been reduced quite a bit by the end of this fight.
I don't understand the whole "vivre card" thing from the very beginning; I mean, it's just a vivre card, Why must they obey Nami just because she's holding a piece of paper filled with BM's life force? Aren't they pretty much going against BM's direct orders? I hope we'll get a logical explanation as to why they can't go against her "vivre card" and why a piece of paper is so important that they'd go against the original owner of the life force being emitted from the card.
I can't believe how powerful the Tankman's "canon ball" is, it took multiple kong guns to break Cracker's clones. Where as, Cracker was sent flying through multiple of these clones and the clones were broken quite easily. The force generated is unbelievable, no wonder Cracker was KO'd from just one attack.
It's because he couldn't beat Cracker that he needed help from others, even in a different scenario, Luffy doesn't have the means get unlimited supply of water. It's not about the scenario, Luffy just can't win the way he is now, that's why Oda went through the trouble of making Nami help him. If Oda wants Luffy to look stronger or as someone capable of defeating him on his, nothing would've stopped him from creating a scenario where Luffy earns victory on his own. Currently, Cracker is simply stronger than Luffy, plain and simple.