What if other teachers behaved like Snape?

[evita2fr]

No: HPFGUIDX 101225

 
> Mel:
> JKR has 
>  intimated that the motivation behind "the prank" was nothing more 
>  than Sirius' hatred of Snape. And Snape sees that as attempted 
>  murder. 

 
> Alla:
> 
> No, she did not. She also said that 'you will learn more about that"

Christelle finds the transcript:

Kyla: What made Sirius decide to send Snape to the Willow?

JK Rowling replies -> Because Sirius loathed Snape (and the feeling 
was entirely mutual). You'll find out more about this in due course.

Ok, it wasn't hatred, but loathing.
 
> Mel:
> DD shrugged it off with the aside 'my memory is as good as 
> > it ever was' back in PoA. He doesn't seem to think THAT wound was 
> > too deep. I shudder to think what the wound James inflicted was 
if 
> > the same DD is saying that it 'runs too deep for the healing. 
> 
> 
> Alla: Dumbledore shrugged it off? Could be, I'll grant you that. It 
> also can be that Dumbledore remembers something about Snape hurting 
> Sirius  so badly that he .... undestands why Sirius did that.


If Sirius's words worth something:


P. 356 PoA

[Remus]"...you see, Sirius here played a trick on him which nearly 
killed him, a trick which involved me--"
Black made a derisive noise.
"It served him right", he sneered. "Sneaking around, trying to find 
out what we were up to...hoping he could get us expelled..."


If Snape tried something really horrible, why Sirius didn't tell? 


Christelle