Re: Harry Potter and The Deathly Hallows - merged
^ The elder wand was actually buried with dd (presumably by snape) when he died, which is why voldemort opened up the grave to retrieve it. yes dd was dying slowly anyway from putting on the horcrux ring, however, the plan was that snape would be the one to kill him, and because it was an 'agreement' between them as such and was planned throughout, it meant that snape did not really 'overcome' dumbledore at all, and hence this way dd would remain the wands owner for good.
What wasnt expected however was when malfoy performed the 'expeliarmus' on dd just before snape killed him, and thats how malfoy overcame dd and unknowingly became the wand owner, something that wasnt planned. Neither malfoy himself, voldemort or anyone else knew about it until the end.
Thats why voldemort killed snape, thinking he was the real owner, but he wasnt. It was this mistake that dd and harry were talking about towards the end. However, when harry overcame malfoy (and 'overcoming' doesnt neccesarily require killing), thats when harry became the true owner of the elders wand and was able to overpower lord voldemort..