I don't think I suggested it was a simple matter.
Fair point!
What I was suggesting was that there is demand for travel between Liverpool and Wales and that if the curve at Halton were to be doubled (or bi-directional) then you wouldn't go to that expense just to provide Chester with a fifth train an hour into Liverpool, you'd do so to provide a direct Liverpool service to Wrexham/ Rhyl etc.
There is probbaly some demand for travel between Liverpool and North Wales, yes. But there were not many through trains in BR days for whatever reason. Is there any evidence on whether through services would attract a lot more traffic on to the railway that is currently put off by a change of train?
I don't want to sound too negative, as I am not a massive fan of the WAG Express and I do think that services from the North Wales Coast should be more geared to places other than Cardiff and Birmingham.
At the same time, I would suggest that Liverpool has declined in importance compared to Manchester, and I would question whether through trains to Liverpool would make any more commercial sense in reality than the through trains to Cardiff.