Prank on Snape

[casmir2012]

No: HPFGUIDX 134526

I did a group search on this topic and didn't find anything, so let me 
know if it's been discussed and what conclusions where made.

Has anyone thought that there was more to the prank played on Snape by 
Sirius, regarding Remus at a full moon in the Shrieking shack; from 
which James saved Snape?  

Theories anyone?  Perhaps one theory is that it may have had something 
to do with Lily?  (I am open and undecided about the whole Snape/Lily 
thing.)

I just get this feeling that JKR gave us that particular memory for a 
reason beyond showing mutual malice between James & gang and Snape.


~casmir