6. No editing of your posts, if you are a repeat offender you will be removed from the game.
Now, one of the biggest problems I've always had with games run on the forum is the ability to PM people. I find it a) removes any reason to chat in the thread after a certain point, b) makes protector roles far too powerful and c) makes it far too difficult for the Mafia to try and ever out anyone, because by about day 2 people already have their little PM groups.
In my game I decided to make it a rule that PMing is not allowed unless your role explicitly says you can do so. So far, that's been limited to the Jailor (although the PM goes through me so the Jailor can be anonymous) and the Mafia roles, or it'd make it impossible for the bad guys. This is the main reason I have the edit rule in place.
Take this situation for example. It's 7PM, someone is up in the dockett and is being asked to claim his role/prove it in order to be proven innocent. Say for instance there's one member of the town (say the Jailor who has outed himself and proven it, then was protected) who everybody trusts, then the only person the person in the dockett needs to prove to is the Jailor, since everyone else will vote with them.
Now the issue arises with if the Jailor and the other player could arrange it somehow in the thread, for the person to out their role and their results for a 10 second or so window, then edit it out it makes it entirely unfair on the other players (especially the bad guys) if they just so happened to not be there at the time of the posting. It then removes any evidence from the actual thread and effectively acts as a PM between the two players.
Now admittedly, it could just be an edit to correct a typo, but after the fact how is anyone supposed to know that?
Another situation to consider is something like what happened with Mini E in the last game. He posted his kill PM in to the thread by accident. Now had he been quick enough and edited it, nobody would've had any clue that he'd made a mistake and he would've gotten away with it scott free. Admittedly that was his first edit, so I let him off with a warning, but still. Say for example a mafia member accidentally outs themselves in the thread, but then edits out the fact so nobody can prove they said it. Is that fair? Not really, a mistake is a mistake.
The rule is there to make people think about what they're posting as well as stop people from "PMing" in the thread. Nobody cares if the grammar is perfect and if there's a typo, it really doesn't matter. People need to be held accountable for mistakes they've made and also if someone tries to break one of the rules by editing, it means they can't as the edit is another rule that they'd be breaking.
I stand by my 3 strike rule for edits and I believe until now it's worked pretty well. There's only been one or two people who've really had an issue with it and I think (especially in your case Drumstick) it was more you worrying about typos than anything else.