@electricmastro:
You expect heavy amounts of development in bonding while a big fight with Kaido is going on and the dome burning down?
No, but little moments that build towards something bigger would be appreaciated. Just like Yamato is doing with Momo.
There's a trope in storytelling called "law of conservation of detail". In essence, you remove meaningless details that won't build up to anything later.
The time Yamato is spending with Momo is time he could be spending forming little bonds with other characters. Yamato and Momonosuke bonding is meant to influence the story later.
As always, as much as I'm feeling more confident about my theory now than before Yamato went to fight Kaido, I can still be wrong. Maybe I am, indeed, and all that time spent is aimed at giving Yamato a bittersweet goodbye to Momo.
However, that still leaves us with no bonds being built with the crew. Usually, the strongest moments come under tension, when characters have to rely on each other. Franky's bonds with the crew were formed mid-battle. Brook's too. Chopper's, mostly. Usopp's… You get the picture. It's really strange that Oda may be waiting the downtime to build anything like that, as quiet conversations aren't as endearing as building trust under action, and partying together may make you like each other, but there's the lack of a deep "I owe this one my life" bond that usually comes from risking one's life for another's sake.
True, even the parts of Yamato "bonding" with Momo have her been talking about things like Luffy's brother, how Luffy is leading the new generation, how shocked she was that Luffy's dream was the same as Roger's, her voicing her trust that Luffy can take Kaido on one on one and not want to burden him anymore, in addition to her voicing to her own Emperor dad that Luffy was the one Oden was waiting for and the Dawn Oden had talked about that he had learned after going to Laugh Tale with Roger.
The thing is: almost every good guy in the story admires Luffy, and even many of his enemies do so as well. Yamato being an absolute fan of Luffy isn't really special by itself. What we are lacking is Luffy reciprocating Yamato's admiration, or Yamato gaining similar admiration from his supposed future crewmates.
That does not mean Luffy doesn't care for Yamato, it's just that we haven't seen him treat Yamato in any special way. Luffy has gotten so many allies in this arc, Yamato feels like just another one for him.
Also, I don't doubt for a bit Yamato's sincerity about wanting to join the crew. If he keeps asking, I have no doubt Luffy would allow him in the ship.
What I'm questioning is the story itself, what it's building towards. Many character arcs in so many different media are about "Wants vs. Needs". A character believes in something and wants to fulfill that, but the journey teaches him that what he truly needs is something else. Sanji wanted to stay in the Baratie, but what he truly needed was to seek his dream. Same with Franky.
The story beats so far have just reinforced that impression that Yamato loves Wano, dreams to be a samurai, and will stay with Momo. It hasn't spelled that out loudly and clear, it's between the lines, reinforced only by repeated beats here and there. But it's what I see in the picture that is forming. That's why I started collecting all the Yamato/Momo moments, as well as the moments Yamato shows some admiration for Wano or samurai in general.