if someone passes me in the middle lane and does get back into the 1st lane, they'll get an unobtrusive flash from me, much like a trucker would do to flash other trucks back into the first lane. I used to do a LOT of driving everyday and it used to drive me up the wall!
I rarely get to worry about it now though, but when motorway driving tuition becomes mandatory we will look back on the days where it wasn't mandatory as utterly stupid. much like how we used to allow smoking in pubs and clubs.
Its just asking for trouble when you allow a 17 year old on the road after they pass their test and say "ok, go for it, the motorway is all yours even though you don't know the first thing about it"
Whats really worrying is those people will be having kids and advising them on how to drive on the motorway. you can just imagine some of the tips
"just stay in the middle lane and don't worry about the other drivers"