In London, who needs to hold anything when another train is possibly just 15 or 30 minutes away?
We are not really talking about trains in London. This discussion really refers to longer journeys involving connections between similarly important trains, or branch line connections off a main line.
To understand what I mean, go to
www.ns.nl and you can put in virtually any long distance journey and see how long the connection times between trains are.
Take for example Amsterdam Centraal to Groningen. There are actually NO direct trains (for most of the day), which would be a scandal if it was in the UK! But if you look at the connection times offered, most of the time you are offered a 2 or 6 minute connection time in Almere and/or Zwolle, ridiculously short by UK standards for connections between Intercity services. So it doesn't really matter that the train isn't direct, you still get a quick journey time despite having to change once or twice.
You could also look at Schiphol to Leeuwarden, Rotterdam to Groningen etc. etc. The whole timetable is designed so you can go pretty much anywhere to anywhere without waiting a long time between trains.
I remember a timetable change leaflet from a couple of years ago apologising that the connection time for a particular journey was increasing to 8 minutes! They did point out that it was only temporary while works were going on.