The pledge to cut the controversial practice designed to reduce delays came as the operator admitted it had been “overused”. Other new measures include pinpointing faults and more effectively deploying staff.

ScotRail’s performance has fallen since August despite a detailed improvement plan being in place for nearly a year. However, Alex Hynes, managing director of the ScotRail Alliance with Network Rail Scotland, said he was optimistic the latest blueprint would fare better.

He told The Scotsman: “I can’t be sure but I can be confident.”

20 point improvement plan unveiled by ScotRail in new bid to tackle train punctuality. Pic: Getty

Mr Hynes drafted in former TransPennine Express chief Nick Donovan to get to the root of the alliance’s problems.

He said the previous 249-point improvement plan, introduced in September 2016, had “delivered great short-term benefit” which was not sustained.

But Mr Hynes, who took over last June, was unable to say whether it had failed to maintain the improvement because it was flawed or had been badly executed.

He said: “It is not easy to answer because I was not here.”

Alex Hynes, managing director of the ScotRail Alliance with Network Rail Scotland. Pic: PA Wire

He described the previous plan as a long list of “laudable day-job actions”.

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However, Labour said Mr Donovan’s report showed it had been doomed to fail because of the scale of ScotRail’s problems.

Mr Hynes said: “I am looking for an improvement in performance that I can sustain into the future.”

Transport minister Humza Yousaf. Picture: Jane Barlow

He said Mr Donovan had worked closely with Network Rail analysts to ensure it was based on “data and fact, not anecdote”.

The cost of the improvements is not yet known.

However, Mr Hynes admitted that even with the plan, it would be “hugely challenging” to reach performance level required under ScotRail’s franchise contract.

This will require the proportion of trains arriving at their destination within five minutes of time to increase from 89.7 per cent over the last year to 92.5 per cent by April next year. It has progressively fallen since climbing to 91.2 per cent last August.

Mr Hynes said improving performance was vital as “the biggest driver of customer satisfaction”.

But he declined to say when the target would be reached.

He said: “It would be a fool’s errand to give you a timescale.”

He said the new plan had already produced benefits for passengers because the number of trains skipping stops had been cut.

Mr Donovan’s six-page report, which has been accepted in full by ScotRail, stated: “I recommend the suspension of skip stopping except as a last resort in service recovery, and then only where the skip stop operation has been put in place before a service departs its origin.”

The report said this should be introduced once steps had been “urgently” taken to ensure trains left terminus stations at Milngavie and Whifflet within one minute of schedule, to avoid wider knock-on disruption across the Central Scotland network.

Trains on the single-track branch line to Milngavie are among the least punctual in Scotland, with just 28 per cent running on time.

Mr Hynes said: “We were using skip stopping to fix a symptom of late-running trains [to minimise wider disruption] , but we should focus on the root cause of the problem. His [Mr Donovan’s] view, and I agree, is that it’s been overused. If we do not improve performance at a few critical locations, the network frankly does not work.”

The rail chief said the review had identified other problem areas such as too many infrastructure faults happening soon after engineering work had been completed.

He said: “That’s a relatively quick win with additional layers of checks.”

Another recommendation is for track equipment to be remotely monitored to provide early warning of faults, such as Rolls-Royce continuously monitoring aircraft engines in flight.

Scottish Labour transport spokesman Colin Smyth said: “These recommendations show the scale of the performance failures at the heart of ScotRail.

“The Scottish Government have been pretending the existing improvement plan was working but these new recommendations show it was always doomed to fail.

“It shouldn’t have taking a former rail chief being drafted in to tell ScotRail that stop skipping was unacceptable.”

Scottish Conservatives transport spokesman Jamie Greene welcomed the “stand-out recommendation” of reducing skip stopping.

He said: “The decree that there should be an end to skip stopping will come as a huge relief to commuters who for too long have endured the pain of missing stations. It is frankly it astounding that it hasn’t been stopped before now.”

Commenting on other recommendations, he added: “There are clearly issues around long-term resource planning and a lack of focus on what timetable changes might mean to resource levels.

“This seems blindingly basic business stuff to me, and frankly comes as a shock.”

Robert Samson, senior stakeholder manager at passenger watchdog Transport Focus, said: “It’s essential the ScotRail Alliance continues to focus on running the trains on time, with few cancellations, less skip stops, and with carriages of the right length.

“These recommendations address some of the ‘behind the scenes’ issues that have come up before, but what passengers will be interested in is the results.”

Transport minister Humza Yousaf, who criticised ScotRail’s punctuality failings in January, said: “Autumn and winter performance from ScotRail was not what passengers or I expect.

“I am sure rail users across the country will welcome these recommendations and a new, more focused performance improvement plan based on the Donovan review.

“The focus on tackling skip stopping will be particularly welcomed by passengers.

“This offers the ScotRail Alliance an opportunity to deliver gradual but consistent improvement and, together with officials at Transport Scotland, I will be monitoring progress closely.”

ScotRail chief vows to ban stop skipping to cut delays