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[Harry Potter HBP] Is Snape a good defence against the dark arts teacher?

The narrator presents Snape as a terrible teacher, presumably because he really wants the Defence against the dark arts (dada) job. Yet most his students seem to do well in Potions, taking O.W.Ls and gaining skills like polyjuice brewing (Crab and Goyle are even making it in the final book).

In spite of hating Harry, he still passes him to advanced potions and with the Prince’s (Snape) old potion book Harry learns more in that year than ever before. But we don’t see much of what is happening in DADA besides essay writing.

Is Snape doing anything in DADA to prepare Harry to fight the dark Lord or go after horcruxes? Is he giving the DA any skills to fight death eaters?
gpt
Snape is a good teacher in the sense that he's a very smart person who can deliver information clearly and answer any questions that come up.  He's a terrible teacher in the sense that he's a bitter bully who will not hesitate to berate students that he doesn't like.  So he creates an environment that's hostile - look at Neville Longbottom.  He's a good enough study with a lot of self-confidence problems.  Over the course of the books he starts to excel in most other subjects as he grows more self-assured, but he's never able to get that chance in Potions because Snape can't actually help someone with personal challenges, he can just tell them they're dumb for forgetting the order of a recipe.  He seems to take a more theory-focused and less hands-on approach to DADA (at least at the level that we see), so he'd presumably be a fine teacher in that sense, though with less ability to inspire struggling students.

Also just a minor note - Snape isn't actually the one who passes Harry's OWL in Potions - those are administered by a separate Ministry-run group who test the students and grade the results.  That being said, he *did* teach well enough that even Harry, who had almost no personal interest in the subject itself, was able to get an excellent grade.