Erm..I don't think so

[pippin_999]

No: HPFGUIDX 125295


--- In HPforGrownups at yahoogroups.com, "ladyramkin2001" 
<sylviablundell at a...> wrote:
 It's more often used to catch a minute to think.  But "I don't think 
so" is often used in  reply to a question so ridiculous that it 
doesn't deserve serious  consideration.We really need a live 
audio copy to get the tone in  which it was spoken.<

Pippin:
As has already been pointed out, it was never spoken. It was 
deliberately typed, by someone who had as much time to think 
about the answer as she wished, and who has been known to 
use   denial as emphasis :

'At the start of term banquet, Harry had got the idea that 
Professor Snape disliked him. By the  end of the first Potions 
lesson, he knew he'd been wrong. Snape didn't dislike Harry 
--he *hated* him.' --PS/SS ch 8.

The vampire question has been current in the fandom at least 
since I joined it, just after GoF. It beggars belief that JKR had 
never encountered it before.

Pippin