How and when did Snape learn Occlumency ?

[delwynmarch]

No: HPFGUIDX 116460


We know that Snape is a superb Occlumens now and apparently a good
Legilimens as well. But when did he learn that ? And who taught him ?

1. It seems accepted that Snape was already an Occlumens back when he
was a DE. But that makes him awfully young ! The only other young
person who we know has tried to learn Occlumency is Harry, and he's
got a real good reason to do it ! What could possibly have been
Snape's reason for learning such an uncommon skill so early ?

2. When exactly did Snape learn the skills ? Was he still at school ?
Was it *before* school ?

3. Who taught him ? Could it be DD ? Would DD teach a Dark Arts kid 
skills as dangerous as Occlumency and Legilimency ? Or was it LV
himself maybe ?

4. Did Snape learn Legilimency along with Occlumency ? If not, which
one did he learn first ?

5. How did Snape learn Occlumency ? Someone (Finwitch if I'm not
mistaken) pointed out that teachers often use their favourite mean of
*learning* to teach. It is also common for people to teach something
specific in the very same way as they were taught it. So could it be
that Snape taught Harry in that weird way (making him more angry at
the start of the lesson) because it was the way he learned Occlumency
himself ?

Anybody have any answers or additional questions ?

Del, who thinks of what it would mean if Snape had already been a
Legilimens at the time of the Pantsing and/or the Prank...