Passengers and bus drivers are said to be "extremely frustrated" by a system that requires drivers to stop temporarily mid-route or drive slower if they're ahead of schedule.
The situation has been highlighted by People Before Smith TD Bríd Smith.
The Dublin TD says the system "essentially demands buses are driven at extremely low speeds or stop at every stop for several minutes to align with the timing required".
She suggested the current situation is the result of schedules being "benchmarked against expected high traffic volumes and busy passenger boarding".
In response to a parliamentary question from Deputy Smith, the National Transport Authority (NTA) acknowledged the issue might have been noticeable in recent months due to lighter traffic on the roads and fewer passengers than expected due to COVID restrictions.
The Irish Examiner reports the NTA expects the waiting times to reduce as traffic starts returning to normal.
However, Deputy Smith told The Pat Kenny Show the current situation is leaving passengers and drivers frustrated.
She said it's a good thing to have systems that ensure buses arrive on time, but this particular scheduling system is "completely inflexible".
She observed: "It’s very rigid, and it will end up discouraging people from using public transport.
“I know one driver who says [when] coming down Church St he has to pull in. Passengers frequently get off and walk the rest of the way into town because this has become a familiar scenario to them."
She said the timings allocated for some routes don't reflect the reality of traffic flow in the capital, and officials now need to "talk to the people who work on the coalface" to get it working properly.
'It’s so frustrating for drivers and passengers'
Sean Yeates, bus driver and Dublin branch chairman of NBRU, also said the current system is frustrating drivers and passengers alike.
He observed: “Historically, bus drivers used to drive from A to B, staying with the rules of the road. Now they’re being asked to stop on route if they’re 59 seconds ahead of a tracking schedule, which frustrates the customers.
“It’s basically a contracted agreement from the NTA and the bus operators in the city. But it’s so frustrating for drivers and passengers - we don’t have the infrastructure here to be pulling buses into the side of the road.
“The city was not designed for large double-decker buses to go around."
He said unions and Dublin Bus have been working to try to find safe stopping points that don't impede traffic, but it’s “almost impossible to do” along some routes.
In terms of the experience for passengers, a message can go out on the intercoms to let people know there'll be a "slight delay to get the bus on time".
However, Mr Yeates noted: “Even that itself doesn’t make sense - we’re going to delay you to get you on time.
"It could only happen in Ireland that you’d have that sort of statement being made.”