Half blood prince etymology

[Brenda]

No: HPFGUIDX 122092


Luckdragon:
At one time there was a discussion of the possibility of Severus and 
Sirius being half brothers. If Sirius's father had illigitimately 
fathered Severus and left him to be raised by an uncaring and 
abusive man it would give credence to Snapes inner rage and 
expressions of anger. This would also give cause for the tension 
between Sirius and Severus.
Half blood could refer to the blood tie between Sirius and Severus 
and as an unrecognized (and last direct line of males )descendant of 
the most noble and ancient house of Black he could be considered a 
prince. With Sirius gone in book 5 it could be that Snape will now 
assume the Black household and the storyline could largely play 
around the whole marauder, Lily, Snape background.

Has the idea of Snape being the HBP been discussed? If so what are 
the thoughts on this?