User blog comment:Supernovalm/Smoker's demise in the New World/@comment-7890302-20140111233922/@comment-130.102.158.13-20140116063601

Luffy didn't 'beat' Crocodile. He was almost killed by Crocodile on multiple occasions but was protected by plot armour. In the end, he found a method of fighting crocodile thanks to the weakness of his DF to liquid. Luffy was given the chance to have multiple rematches, and find ways to defeat his opponent eventually.

As for Moriah, as mentioned, Moriah grew fat and lazy. He was even deemed too weak to be a Shichibukai. Even so, Luffy didn't actually defeat him. The entire Strawhat crew worked together. Yeah Luffy did most of the work towards the end, but he had nightmare Luffy mode, which was essentially the power of (was it a thousand? Or a hundred) individuals combined.

So yeah, comparing Smoker's fight to Law, Vergo and Doffy to Luffy's fight with Croc and Moriah is really apples vs oranges