Theories...a load of waffle ?

[Inge]

No: HPFGUIDX 173762

Anne:
> 
>   Yes!!  Crabbe...he called the diadem a "die-dum" and then he did!  
Die dumb that is, but he lived dumb so I suppose it was fitting ;)
> 
>   Not to mention Grimmauld Place, which was indeed a grim, auld
(Scottish for old) place

Inge:
And then of course there's the connection between Trelawney seeing the 
Grim and Sirius' childhood home actually named Grimmauld Place - so 
maybe once again Trelawney actually had it somewhat right :)