I'm playing the Game of Thrones conversion mod and because of the way the provinces are set up, it's very easy to have individual levies larger than my entire fleet. I know you can create multiple groups of levies by assigning the levies of each barony to a different group, but is it possible to split the levy of a single barony?
i.e.: Playing as a Greyjoy count, one of my castles can produce a levy of 2,000 troops on its own while I can only raise 16 ships total. Since I can't find a way to split them, there's no way to get those men to the mainland, even with multiple trips. Only being able to use the forces of my vassals, who have smaller levies or will not let me levy their entire force, dramatically reduces my military power.