I don't understand Dumbledore's rationale to have Snape teach occlumency to Harry
My understanding is that Dumbledore's rationale for having Snape teach occlumency to Harry is:
- Snape is a better Occlumens than Dumbledore
- Dumbledore didn't want Voldemort to know how important Harry was to him
While the first one may be true, but it's weakened by the fact that
- Snape is a horrible teacher in general (unless you're in his house), which has 15 years of evidence behind it
- Snape is a horrible teacher to Harry and friends in particular, which has 5 years of evidence behind it
- There is 5 years of personal animosity between the two
- Snape has a history of bad memories with Harry's parents, which may be exposed by the training
The second one just makes no sense. Dumbledore knows Voldemort wants to kill Harry. Likely with some torture for the first defeat.
If Voldemort knew Harry was important to Dumbledore, did Dumbledore think Voldemort was going to double kill Harry or something?
All that combined makes Dumbledore's choice go from a mistake to pure stupidity and incompetence.