uh obito isnt the one who knows as much jutsu closest to the sage in fact i think that goes to orochimaru it is his goal to know every jutsu...itachi didnt lie to akatsuki about his allegiance as shown obito was true leader an knew full well what itachi was up too, he might have fooled the others or most likely they didnt care as long as mission was complete....but it is a very good argument but obito wins because his plans have worked, itach's plan to change sasuke failed well its still in the process and itachi's plan to kill obito failed because amterasu failed so...yea obito gets this although there are smarter shinobi like...
madara because everything obito knows is because of madara and shikaku is the or was the genius behind the alliance forces or minato for easily figuring out obito's power and effectively coutering him instantely what still takes naruto and everybody else took him only seconds to do...