Even if he trains how to stop a takedown 24/7 until the fight hes not even gonna be CLOSE to stopping the takedown of someone that has the calibre of wrestling that couture has.
Rogan explains alot of stuff is that video also that boxing fans doesnt understand. How he has to change his stance, be afraid of takedowns/leg kicks, he cant even have even Close to the same stance as he has in boxing or even couture will break his fucking legs..
And without the same stance everything fucks up, the power/counters etc, he has to adapt ALOT which he hans't got time for lol.
Couture could pretty much just tuck his head and rush him and whatever 1 punch toney has the time to do wouldnt come close to ko'ing him.