12 Uses for Dragon's Blood -Major Clue or red herring?

[kneazelkid]

No: HPFGUIDX 71206

Susan Smith (A.G.) wrote:
Just curious-does anyone know the 12 uses for Dragon's Blood?
Hermione was reviewing them for an exam in OOP; and Dumbledore is 
credited with their discovery in SS. 
Too, does anyone know why JKR is fascinated by the number 12?  Is it 
because she is a fan of numerology as some have said?  Or is she 
trying to give us the greatest hint of all?  We see it as a "magical" 
number throughout all 5 books...

me:
I have heard a lot about the number 12 and 13 in these books. This 
may be sort of a magic-killer but, anyone else think that it may be 
arbitrary? I used to date a guy who was a big fan of Star Trek and he 
told me that the big joke was that whenever someone would talk about 
their past, the event they were describing would always be "12 years 
ago." (I think it was 12 anyway -- not a big Star Trek fan). I think 
12 was used because 10 is too round and obvious but twelve is a good 
long-ish number (not too big, not too little). I know several writers 
like to have little coincidences that don't have specific meaning 
other than comfort for the writer (Stephen King's use of Derry, 
Maine, for example).

Kneazelkid -- who is already anxiously awaiting book 6