Still happens. I was driving the M4 in S Wales only two days ago, pulling a caravan, cruise contol at 60 (legal limit for towing), when an artic heavily laden with steel rods passed me at about 75 on a dip, then slowed to about 50 by the time he reached the next hill brow. He and I were counter-overtaking each other on the hills and dips for about the next 5 miles, me at more-or less constant 60.When I started driving trucks used to rush the hills and would quite often pass you at 70 in the dips before you passed them again near the top of the hill getting slower and slower.
Other trucks were having the same effect but less pronounced, varying between about 55 and 60. You notice these things more when your own limit is 60 and you are therefore mixing it with these guys. I was not overtaking them unless I had at least a 5mph difference BTW.
