OOP: 'Dung' and Crookshanks etc.

[Alon van Dam]

No: HPFGUIDX 65786

[wonders whether or not there's still a spoiler-line policy]

You know... The more I think about the Dung = Crookshanks theory, the 
more I like it. There's only two major flaw with this theory: 

1) Their personalities are nothing alike. 
2) It's a bit of an old plotline, no? Unregistered Animagus? 

Of course, it could be that he's a registered one, but I doubt that 
Hermione would forget that. 

The two major points in favor, in my eyes, are: 

1) Their appearances are basically described identically (bandy-
legged, long ginger hair, shaggy)
2) Dung is unshakingly loyal to Sirius. Remember when he was asleep 
at Grimmauld Place and wakes up with a start, raising his hand in the 
air and mumbling "I agree with Sirius". 

I don't think I need to remind anyone how instrumental Crookshanks 
was to Sirius during PoA. And, yes, of course I've entertained the 
thought that Crookshanks was an Animagus, especially seeing as how 
antisocial he was in the pet-shop to anyone who tried to buy him 
before literally throwing himself at Hermione. And, though I don't 
find it incredible that Wizards could learn how to talk to animals, 
I'm pretty sure we'd have heard more about it if was a big thing. 
Hagrid, for one, would have perfected it, and we've heard nothing of 
it. How, then, was it possible for Sirius to communicate such things 
to Crookshanks as 'Go to Gryffindor Tower and find a way for me to 
enter it, remembering that it requires a password'?

On the other hand, I kinda liked the idea of Crookshanks actually 
being what he seems, a normal cat who's quite smart.

Thoughts?

Alon, signing out for the night