Snape outing Harry as Parselmouth (was Re: If DD knows, then why..?)

[Eustace_Scrubb]

No: HPFGUIDX 93967

Susan asked, before rushing out the door:
Can I show that I've likely got a bad case of movie contamination
here? [Eeeek!!] *Do* we know that Snape told Draco to use the
serpentsorcia spell [I've butchered that spelling]?? It's certainly
not clear in the movie and I don't have my book here to check.

Eustace_Scrubb happened to have the book at hand:
This is what happened between Malfoy and Snape prior to Draco's use of
serpensortia(on p. 193, US pb ed. of COS):

"Snape moved closer to Malfoy, bent down, and whispered something in
his ear.  Malfoy smirked, too."

Then Harry tries to get Lockhart to explain blocking again and there's
the "Scared?" "You wish" exchange between Draco and Harry; then
Lockhart counts to three and Draco casts the spell.

So we don't know what Snape said, but it would be a reasonable
inference (but not the only possible reasonable inference) that Snape
suggested serpensortia. 

What I want to know is how many 2nd years can do a competent
serpensortia?

Cheers,

Eustace_Scrubb