Actually, I’m just checking to see what actions can cause a post to double up…
The back button…
Well, not that, apparently.
Let me try this again.
The back button
Refresh…
How about postus interruptus…
Nothing!
I AM IMMUNE TO DOUBLE POSTS!
HI-HO SILVER!
Nothing!
I AM IMMUNE TO DOUBLE POSTS!
HI-HO SILVER!
Double-posting is easy. 
Ok, no it isn’t. Shaddap!
Okay, maybe this’ll do it…
Oh this is ridiculous. Why won’t this thing double post???
It will get you when you least expect it …
MWAHAHAHAHAHA!!!
Or … when the hamsters judge that you’ve tempted fate too long …
Why, oh why do the hamsters mock me so??
And somewhere, in the depths of the control room, the hamsters chitter and cackle wickedly … 
My basic observation.
After you compose your post you hit “submit.”
When the board is busy, quite often you get a message that says something other than “thank you for posting.”
DON’T BELIEVE IT!
You just posted.
Once you hit the “post” button, let it go. Don’t do ANYTHING until you go back a read a new, refreshed version of the thread. Your post will appear there 99% of the time.
When you hit “submit” or “post” or whatever the hell it says, just assume you posted. You almost certainly did.
This odd mirror thread is just … freaky. Shows on the main page as having the same OP, yet … doesn’t.
Woah.
Yeah, I noticed that a little while ago, Ice Wolf. I *think[i/] a mod must’ve been deleting those four posts and got distracted. Spooky.
See?? This is the kind of thing when you shake a fist at the Sacred Hamsters[sub]TM[/sub]! Oh, woe!
Don’t mind me, I’m just heading for the nearest high hilltop, before th’ deluge …