Mike,
I realize that Maeda was kodokan judo through and through but what about his world travel fight experiences(before landing in brazil) with wrestlers,boxers,and strongmen?
It must have influenced what he taught and how he taught the Gracies?This I believe is the difference between kodokan judo and BJJ.While kosen judo developed it's highest levels under a special randori curriculim set up for kodokan mat experts.
All in all,it all it starts looking the same if the rules are somewhat similar.As Mat hughes proved with his fight with Royce Gracie.