How did Dumbledore Win the Duel?

[Bart Lidofsky]

No: HPFGUIDX 175841

Bart:
I'm going to get a bit Sherlockian here: Once you have eliminated the 
impossible, what you have left, no matter how improbable, must be the 
truth.

Points I am taking as given (either canon or simple logic):

1) The holder of the Elder Wand cannot be beaten in a magical duel.
2) It's been establshed that wizards, IF PROPERLY PREPARED, cannot be 
injured by muggle means (look at the description of real wizards and 
witch burnings).
3) It has also been established (for example, Quidditch injuries, the 
fistfight with Draco in OOP), that wizards are vulnerable to normal 
physical injury if unprepared, although the injuries tend to be trivial 
to cure.
4) It's hard to concentrate when someone is whacking your head with a 
baseball bat (there is no canon to support this).
5) Magic generally requires concentration, although we have one occasion 
where a wand DID act on its own.

So, here is my idea of how DD won the duel with Waldo: He used PHYSICAL 
means to disarm him.

Bart