Nature of Patronus - Snape's Messenger Patronus

[Steve]

No: HPFGUIDX 182614

---  "potioncat" <willsonkmom at ...> wrote:
>
> 
> > Jerri wrote:
> > I do wonder how Snape is supposed to have communicated with 
> > Grimauld Place ...
> <snip>
> 
> Potioncat:
> It's not a popular explanation, but I think is one of those 
> moments JKR referred to in which she had painted herself in 
> a corner. I'm not sure if she noticed, though.
> 
> In PoA DD tells Harry that the Order has more efficient means
> of communication. And JKR confirmed (I think) that the method
> was Messenger Patronuses. So I think it was pretty clear that
> JKR was thinking that Snape had sent a Messenger Patronus to 
> 12 GP.  Only, that doesn't work if it would reveal to everyone
> that Snape loves/is-devoted-to Lily.
> 
> ...

bboyminn:

Well, I think there is one thing the people are forgetting, and
that is, very likely, many people have the same Patronus. I
mean, there are only just so many realistically available animals
in the world. Many people are bound to have a Dog Patronus, 
but just as every real dog is different, so to would every
dog Patronus be different. 

The same with a Stag, I find it hard to believe that Harry is 
the only person in the world with a Stag Patronus. So, while
people may have known Snape and Lily both had Doe patronus's
I don't think that would have been anything other than a mild
point of curiosity.

Also, consider that amoung the Marauders, unless they were 
blind and stupid, they must have realized there was something
between Snape and Lily. Exactly what that 'something' was I
don't think was clear, but James and Sirius meet Lily and
Snape together on the first train ride to Hogwarts. Snape
maintained his friendship will Lily until it became clear
that Snape was 'hanging with a rough crowd' and Lily couldn't
accept that.

Further, if Snape's Patronus CHANGED to a Doe, would that mean
he was incapable of casting his original Patronus if he will 
it to be so? By that I mean, if he spontaneously casts a
Patronus, it comes out a Doe, but if he consciously and
willfully cast his Patronus, he can force it to be his original. 

So, two points, I don't think it's uncommon to find individuals
with similar patronuses. It would be a curious event, but not
an unheard of.  Next, if a Partonus can change, does that 
imply some possibility that a person can willfully cast a
Patronus in more than one form? Keep in mind that Snape was
a brilliant wizard who was extremely knowledgeable in magic
spells. 

Lastly, completely unrelated to the current discussion, but it
was a pretty cool trick when McGonagall cast THREE simultaneous
Patronuses in Deathly Hallows, and sent them to warn the three
heads of house. How handy would this be if you were being
attacked by a gang of Dementors? 

Is that something anyone can do with reasonable practice or is
this unique to those who are personally brilliant, and extremely
knowledgeable and experienced in magic?

Just a few Patronus thoughts.

Steve/bboyminn