That's good to hear then. Least train from Bolton can have an extra green signal (of course a few signals back) and not have to faff waiting for platforms.
That's the main benefit I agree.
A notional future final layout for Salford Crescent could be a twin island arrangement with an extra track threaded through the University Road West bridge under the station entrance building and main road.
This would be a back face for the new platform 3, which already provides all the access needs, though significant public road and pedestrian bridge alterations would be required to fit around the changes for a 4th platform. Crescent northbound would need new surface turns to replace the underpass for access to the University. The road looks wide enough to accommodate extra turn lanes if required. A single lane road or a cycle/pedestrian path might still fit alongside the new track through the wide underpass. The old signal box building would be removed, with any operational signalling, comms or power equipment within relocated.
My ultimate layout would use both Atherton and Bolton routes, which run fairly closely parallel for a mile or so before diverging, to create around a mile of four track infrastructure, paired by direction, between Salford Crescent and a new grade-separated junction complex near Agecroft. Here a rerouted Manchester-bound line from Atherton flies over a new rerouted Bolton-bound line and joins the Manchester-bound Bolton line for the run into Crescent station. So both NBs would be accommodated on the former Atherton line, both SBs on the former Bolton line.
A matching grade separation is provided south of Salford Crescent station.
Here's a track and signalling layout with a notional very high intensity service pattern simulated.