For anyone who thinks its literally IMPOSSIBLE for the NBA to be rigging a series (what an idiot you are), please just exit... I could show you a book full of the scripts written, and you wouldn't believe it...
So, for those who know it's a possibility... How's this for a theory:
When Duncan knocked off Lebron's headband "accidentally", the ball was no where close to his hand... In fact, if you look at the video, it looks like he simply reached his hand up, and knocked the head band off on purpose... He wasn't going for a block... i don't know what the hell he was doing...
This could have been the signal for the spurs to stop playing defense, and for Lebron to go ape shit and make a story book ending... (Jordan had the Flu game... Now Lebron has the "Headband Game"... and we have $25million more dollars off the buzz of his "headband"... brilliant - David Stern) ..
(This scenario is hard for me, because I don't believe Timmy was in on the Fix, but I know Pop was 1,0000%... but I'm just throwing this out there just to tickle your brain... Perhaps you can give a better explanation for Duncan knocking his headband off)