I’m wondering about why I’ve seen a lot of them. I’ll share my data and see if it helps…
It’s Friday, June 23, 2000 12:25pm, Central Time. I was posting in MPSIMS to the Dopeville thread. It gave me a connection timed out error. I attempt to reload via the “Refresh” in IE 4.whateverthisnumberis. I finally get back to the thread via back button, to see I’ve posted twice.
I’m assuming that when it says Connection timed out, it’s posted the message, and when trying to reload, it posts it again.
Hope this helps.
Mostly double posts happen when for some reason the system times out and the poster hits the button a second time.
It’s tough to trust the system. I’m sure nearly everybody here can tell of a time they made a GREAT post, hit the button . . . and it vanished, never to be seen again.
However, I would be willing to bet these selfsame folks have had double posts too. You just don’t know when the gremlin will strike.
your humble TubaDiva
Administrator
Already had one great one vanish, then decided not to bother reposting, as I’d lost interest by that point. 
When in doubt, I hit the “back” button, copy the post into a file, and wait a day. If it doesn’t show up after 24 hours, I’d say that a double post is a reasonable risk to take.