Monster train

In the USA, across vast distances, it is common for a train to pull along wagons trailing a mile back, but in this country it is an altogether rarer sight, especially with regard to passengers, station length being a major constriction.  While changing trains at Bromley South, as my connecting transportation arrived, the automated station announcer mentioned how this train would be dividing in two at Faversham, "The front 12[?] carriages will go to .... and Ramsgate; the rear 8 carriages will continue on to... and Dover Priory."  20 carriages!  SouthEastern (or whatever the franchise/government-owned operation is these days) have inauguated a super train.  I was wondering at the kind of engine needed to power this behemoth.  Letting Kimberley run pretty much the length of the train (I would then count the carriages passing me by after I got out) was in the end unnecessary - apart from tiring her out, that is - as when we had reached the the head of the front carriage, the driver announced over the Intercom that were indeed only 12 carriages, dividing equally at Faversham, confirming my suspicions about an engine that powerful to haul 20 of the things.