Two problems on the GN route.
1. Balancing the long distance commuters from North Cambs with those in Herts. It doesn't work, Peterborough is too far away and those living in Stevenage and south of Stevenage suffer to allow those who chose to live so far away (as many have done) a better non stop service and readily available seats.
And don't get me started on Kings Lynn and the Fen Line, seriously that distance is too far to be considered along side those closest to London, but they waste valuable paths and those services could be provided by a regular Cambridge northwards shuttle.
If GN/TL ran a fast in peak hours KGX to HAT and WGC (reverse in morning etc) that would relieve a huge load and probably account for 60-70% of the peak load at 17.52.
Skip Finsbury Park, but to make up for that you run a twice hourly 717 fast from Moorgate to Potters Bar, Hatfield and WGC.
However it won't happen as GN persist in running the fasts to Peterborough.
It's almost as if they have a time that a journey must take and try and average it out so not to upset those who commute further. It's your choice to live that far away why should it be us further south that need to suffer?
2. The second Digswell Viaduct.
Those 'in the know' know that this will happen, but Grant won't risk his marginal seat by talking about it just yet.
By 2025 it will be under construction.
Until then the capacity issue won't go away, it should have been started in 1998 I recall, what a missed opportunity.
And for those who don't know Digswell.
https://anonw.com/2016/03/14/could-we-just-double-the-width-of-the-digswell-viaduct/