Is Percy a Spy?

[templar1112002]

No: HPFGUIDX 110993

Hello, my second post here...

Due to JKR's site congratulating Percy on his Birthday, I've read 
many comments (not in this site) theorizing that Percy could be a 
spy for the Order.  Forgive me if this has been discussed before, 
but I run a search and nothing came up.

As I said, many people think that Percy is actually spying for the 
Order of Phoenix.  I can see why they think so, it could really be a 
very smart plot twist.  But I can't help seeing too many plot holes 
with that theory.  Let's assume that Percy is in fact working under 
DD's orders. These are my doubts:

1) Why is he keeping that information secret to the rest of the 
Order members, including Arthur and Molly?
2) If Molly knows about it, why then did she get soooo upset when 
Percy returned her sweater?
3) If everybody in the Order knows Percy is a spy, except 
the 'children', why would Percy write that wretched letter to Ron 
about Harry?
4) What was the gain/profit of that letter?
5) If Percy is indeed a spy, why didn't he warn DD about 
them 'visiting' Hogwarts when the DA was discovered?  Why didn't he 
warn DD about the change of time for the trial hearing? (after all, 
the rest of the Wizengammot whatever members were all there in time, 
Percy must have known about this change in schedule well in advance 
to warn DD, yet DD was late, barely made it)
6) If nobody knows he is a spy but DD, why keep it secret when 
everybody, including the 'children' know about Snape being a spy to 
Voldemort?

I am sure there are more holes there, but for now I'll post these.

What do you think?

Marcela