You keep mentioning that first Wanderlei fight but again thats a VERY green Crocop months into a part time MMA career, I don't think you really see him start to devolp his takedown defence until the second Fujita fight and tis not until 2003 it really looks good.
I would say Nog's double leg brust wasnt always consistant, some of that werent amazingly timed BUT some of them were, he was fast for a HW and did link them into his striking quite well, Ironically Mirko probably caused him the most problems because he couldnt enguage him much due to how effective his body kick was.
Good movement for striking doesnt automatically mean good takedown defence either and honestly I don't think we've really seen Gane tested in terms of extreme ability, so far he's basically just been able to slowly control distance he's not had to show deal much with guys really pushing forward fast against him either for striking or grappling.