Snape could've used other 2 unforgiveables

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No: HPFGUIDX 135851


If this has been brought up before, please ignore. 

I know Snape said words to the effect that they were
not to kill Harry because Voldemort wanted to do that.
But if Snape is so evil why didn't he use one of the
other two unforgiveable curses on Harry. They wouldn't
have killed Harry. And Snape also doesn't curse Harry
until he's unable to control his rage any longer. It
seems as though he just wants to leave and not hurt
Harry, but Harry gives him no choice by pursuing him.
These things make me think that Snape is still on the
side of the OotP.

Cathio