Editing is changing a post's content in any way. I don't have any specific examples in mind but I had the impression that you went further than adding spoilers which was apparently wrong. Sorry about that.
This is exactly what I meant though, as a normal user I can't keep track of what you do at all.
It's fair to assume if a post is edited that the original user did it. I'm notorious for editing all my posts a thousand times.
If you do have a specific example at some point, I'm happy to chip in to tilt the system towards or against something, but almost all deleted posts are run by the uploaders first anyway; and all bans have to be done manually by the administrators.
I haven't seen most of the edits so I can't say anything about that, but I've been thinking something similar for a while now regarding deleted discussion posts (considering I've been a part of a few of them myself). I think it's fine to put a stop to a discusion that's out of hands, but most of the ones I've seen are merely getting heated. Discussions are bound to be heated and I personally don't see a problem with this. Being stopped halfway frequently puts a damper on things.
I'm very curious to hear more! Would you mind e-mailing me, or dropping by IRC some time (preferably not today)? The point is never to stop discussion, it is to stop personal attacks, and inflammatory commentary that discourages others' from posting. This is really very rare - I can't think of it happening once this year.