So why did the lords that only provide supplies lost the most? For loyal lords it's clear, but I don't see any hints on what he's hinting at.
I can guess, good reputation and experienced soldiers are probably pretty good gains (not sure how to weight it against the loss of resources though), but it's nothing concrete.
Maybe they give out a lot more supplies than they should've? The guy in the book is probably for hinting that, but I can't tell for sure.