I'm with Elle, I hadn't the slightest idea what you were talking about!
However, both Chris and Rossim explained things very well. We are going down to breakfast soon but I'll get the laptop out when we come back up to the room and have a little experiment with dud posts to see what happens.
Edit - I posted two duds, one of which is left, they were Nos 16 and 17. I deleted No 16 so No 17 moved to No 16 spot, on the main forum screen it is showing as 15 replies. Interesting and helpful in the current circumstances.