Lorries tailgating one another on motorways is often said to be due to them wishing to travel in the 'slipstream' of the wagon in front, although it leaves them with practically zero chance of stopping if that wagon hits the brakes hard.
The tailgating through 50mph roadworks is a depressingly well known issue, and happens because lorries are limited by law to 56mph. This happens to be about the speed you'll get away with in a 50 without being ticketed, and so leads to less professional drivers choosing to steam through with their foot hard down (the lorry won't go any faster once it tops out at 56), taking offence at motorists who choose to stick to the limit. It's an appaling driving habit with real potential to kill people, any anybody caught doing it in a 44 ton lorry deserves removal of their licence!
A related pet hate of mine: when the speed limit signs are put up on Smart Motorways and (one or two) HGVs ignore them.
One recently on a 4-lane "smart" M-way, the "40" mph speed limit and "lane 1 closed ahead" red-X sign came on, I was in lane 2 and slowed to 40mph (didn't pull into Lane 1 as it was showing red X on sign). Next thing is as I passed the second sign saying 40mph and lane 1 closed, I have a truck up my rear aggressively tailgating and blaring his horn because I was only doing 40mph...... he overtook then dropped into Lane 1 not having slowed down.... and not much along further with the proper overhead gantries with speed cameras he finally realised he'd better slow down and get into lane 2 and aggressively forced his way in..... I am not sure whether he missed 2 lots of restriction signs of the type that are alongside (not gantries) or if he felt the rules didn't apply to him.
Not much further beyond the gantry, a Highways Agent vehicle in Lane 1 was behind/escorting a damaged vehicle along the carriageway to the next refuge at maybe 10-20 mph. That was why the lane was closed.
It took the HGV muppet drive three sets of signs before he responded. You can see how people get killed on smart m-ways.
I am no longer happy driving on some types of Smart m-ways; the M42 way of doing it (normally 3-lane m-way with hard shoulder but when busy and speed already resricted, opening up the shoulder for running, lots of refuges and sensors) seems OK, but I have had 2 or 3 occasions on the 4-lane no-shoulder stretches of the M1 of coming across a vehicle stranded in Lane 1 with no signs yet switched on, it really makes your heart beat a bit faster even when you see them stopped a long way back there's not much time to respond.
My other bugbear is the A42 between Tamworth and the M1. It's 2-lane (dual carriageway) and HGVs are not allowed to use the outside lane between 7am and 7pm. Doesn't stop them though, they elephant race with long "overtakes" with a less than 1mph differential if any taking two or three miles to pass another truck at times. If there was a camera there it would get evidence of loads of trucks in breach of the restriction- even vehicles owned by "reputable" companies such as Stobarts.
Whilst the majority of HGV drivers are very good, there is a persistent minority who really let the side down.
TPO