Ashford station to Chart Leacon is 90mph, Chart Leacon to Postern is 100mph, Postern to Tonbridge is 90mph. The bulk of that is Chart Leacon to Postern at 25 miles so a simple calculation with a 'small margin for error' would suggest it possible to complete that section in 17 minutes so Ashford to Tonbridge could be done in less than 21 minutes. Add in a Paddock Wood call and it's probably only 25-26 minutes even with a 1 minute dwell time.
I know i'm quoting an older bit of the discussion, but there was a good example on Thursday (4/10/18) night of how quickly a train in passenger service can make the journey between Tonbridge and Ashford without making any intermediate stops.
I was on
2R78 (the 2210 London Charing Cross to Ramsgate), which picked up a 36 minute delay at Sevenoaks due to a passenger falling ill and needing the attendance of the ambulance service. Due to the length of the delay, the following service (
2R80, the 2240 London Charing Cross to Dover Priory) caught up to it and overtook.
What followed is honestly what i'd consider to have been a good use of skip stopping to improve things for passengers. It was announced that 2R78 would be running fast from Tonbridge to Ashford, but that 2R80 would be making all intermediate stops as usual. 2R80 which had overtaken was routed in to Platform 2 at Tonbridge instead of Platform 3 as usual. It was then held there for a short while as 2R78 followed and went in to Platform 3. Any passengers on 2R78 could then transfer to 2R80 (if they hadn't already at Sevenoaks), whereas any passengers for Ashford and beyond could remain on 2R78. 2R78 was then dispatched first, and had a fast clear run to Ashford completing the journey in 23½ minutes instead of the regular 38 minutes - reducing the delay on departure from Tonbridge of 38 minutes to just 23 minutes upon departure from Ashford. I'm sure this is something that passengers who were travelling further afield were grateful of, especially given the late hour, and it didn't cause a tremendous disadvantage to passengers who wanted intermediate stops (beyond picking up a small delay and having to change trains). I've attached screenshots of the relevant bits of the schedule from RTT for anyone reading this in the near future when the data has dropped off of display on RTT!
Needless to say of course, hopefully the passenger who was taken ill was able to receive the appropriate medical attention and is now doing well.