But again, why even have the remotest chance that Picard could come to danger? Why not just bury B4 on an uninhabited planet? Shinzon needed Picard's blood to survive. If I needed someone's blood to survive, the last thing I'd do is send that person on some wild goose-chase where there's even a small possibility that said person could be hurt or killed.
Yes, that's a fair point. I'm just saying what I think the filmmakers' intent was, but I agree that the whole Kolarus sidebar was a bad idea.
Maybe they should've gone to Romulus earlier in the film to enter into peace talks with Shinzon, and had to fight alongside Shinzon to fend off an attempted countercoup by militant Romulan loyalists who were trying to use B-4 to impersonate Data and infiltrate the peace talks. That would give you an early action sequence serving to introduce B-4 into the story, one that would serve a story purpose by reinforcing the early bonding between Picard and Shinzon and the hopes for an alliance. Then, during the sequence where they're studying B-4, there could be some throwaway exposition about how Romulan intelligence came into possession of a Soong prototype. And it would later turn out that the loyalist attack was actually staged by Shinzon to get B-4 onto the Enterprise. Or something like that.
I'm thinking TPTB should have consulted you before filming started. Much better idea than what we got on screen.