My trip back to Pembrokeshire every Tuesday would usually pause outside Swansea, accompanied by a message from the guard stating that we "were awaiting a platform". Shortly afterwards, a train would depart from Swansea - a short 2-car DMU - and we would enter the platform and disembark.
Only my onward connection was that short 2-car DMU, and a number of us would form a deputation to the station office, where someone would resignedly arrange for a taxi to be available at Carmarthen to pick us up from the next (and last) arrival at that station to take those of us not wanting the boat train to Fishguard to complete our journeys.
So, no, it doesn't always happen, but I guess it's easier to enable it when you're not in a complex network where delaying one train has a potential knock-on effect across a wide area, as it would in a more built-up area, perhaps.