That, or for someone to tell me that it already has it, and I'm Doing It Wrong.
A thought on derailing: people don't actually run on rails. Trains run on rails, and if they come off them then you are going to be very late for that meeting. But people are all-terrain vehicles. It doesn't matter how contained you attempt to keep the debate (though the off-topic is easier to identify and deal with according to agreed procedures the more contained the forum), the participants are free to wander the highways and byways according to their own lights and you can't stop this. You can force people to shut up, and I see that some people are very keen on this, but you can't force people to keep talking.
"Derailing" on the internet isn't a teenage vandal throwing the switch at the points and sending the Intercity train hurtling off the rails. It isn't even the result of cheapskate contractors cutting corners, or failure to follow-up reports of hazards*. It is the choice of ways where the route divides.** Even railway lines have freight loops and fast loops and "Oh dear God, we're going via Retford" loops***, routes crossing at Birmingham, and those weird bits when you find yourself reversing out of Reading. Railways are networks, and ultimately the single track leads only to the buffers. The Night Mail crossed the border. Dr Beeching is not remembered with unalloyed gratitude.
*Incidentally, I was interested that this incident on the Dublin-Belfast railway bridge scarcely made it into the mainland British papers - I learnt about in when I was in Ireland a month after it happened. Yes, it was a near-miss, but "Tay Bridge Disaster Mk II" is a pretty big near-miss. Mind you, these things are surprisingly common. My mother warned us against one local line for years due to badgers undermining an embankment, apparently notorious in planning circles.
**This applies even when it is the troll coming into a discussion and saying "But what about [X]". Yes, it is almost teeth-grittingly impossible not to engage, but doing so is still a choice.
***It was the diversion via Castleford on the return from Nottingham that pretty much clinched my decision not to attend the university.