I honestly think that the reason why Shanks never made a move before is because he knew from the start that without the nika fruit (that he actively stole from WG) there is no point in going to Laugh Tale, he would end up being "too early" just like Roger. Think about it, he started moving right...
Hi to all, I'm new to this forum but I'm following it from long time.
I think that as some other members has pointed out, before Roger's era, Big Mom and Kaido used to be in the same crew. "Rocks" could be either the name of their captain or the name of the crew. Anyway the Garp defeated this...