MWPP and ...Snape?

[Jacinda van der Merwe]

No: HPFGUIDX 88818

Regarding Harry seeing his father in the penceive and deducing he is a Gryffindor.  I don't think he will make such a huge mistake and from JKR's side, that would be quite the false trail to lead us on.  She doesn't cheat.  They will have to explain, in great detail why Harry mistakenly tought his father was a Gryffindor.  
 
What I would like to know though (I missed the origin of the discussion) is what repercussions would it have if James, Sirius, Lupin and Peter were in fact Slytherin?
 
SabrinaPotter (no relation to 'the boy who lived')