Re: Hit the rear end of the fire-truck ? ... happens more often than you'd imagine
"How often have you been closing on a sea of brakelights slowing gently to match speed with the traffic going at an expected pace, only to suddenly realise that it's not moving at 30 but stopped dead?"
Myself? Precisely never. A quick poll about the place just now (10 adults) suggests what you describe is not common at all. We can all see (some with the help of glasses/contacts) the difference between slowing and stopped traffic from a couple hundred yards.
Should you be driving? Might want to get yourself checked out just for your own piece of mind, lest you inadvertently kill somebody.