The V1 times from Leigh bus station to Manchester Albert Square vary considerably. In the morning peak it is 55 mins or 60 mins according to the timetable. The maximum is 62 mins for the 08.20. However if you go at 04.00 you'll be there in 35 mins. These are the timetable figures if it runs to time.
Leigh was my home town until 1972, and from 65 to 72 I travelled to school in Salford every day.
When I tried out the V1 recently at 15.00 one afternoon from John Dalton St it took 60 mins to Leigh bus station. It was also very bumpy on the busway but I was on the upper deck.
I wonder how much a new rail link from the Atherton line west of Walkden, cutting across to the old Tyldesley and Leigh trackbed would have cost in comparison to the £15 m busway. Even a single station seems to cost Network Rail £20 million these days.
You'd need to assume that central Manchester had the rail capacity to accomodate the extra services needed to serve such a spur.
Problem is that the demand isn't just Leigh - its Tyldesley, Boothstown, Astley etc. all on the same corridor.