Well as much as I am loving the unleashing of frustration, something of a national sport at the moment, it is actually my first post ever about the S&C.
The bit I am really interested in is a cost benefit analysis as a performace on a line like this v 158's, more an an example as it is a simple line in terms of fairly long electrified stretch, fairly long diesel stretch with gradients and stations. To me the calculation would be rental cost v a pair of 2 carriage 158's set against the lower fuel consumption of running under the wires plus presumably better efficiency of the newer engines over a longish run plus whatever the delta is in maintenance costs. Probably nobody on here is able to answer this question and it would need the developers of the concept to run the calculations.
Running these sorts of calculations is going to need doing a lot more as we contemplate lots of different mixed traction options and I for one am quite interested in all the geeky graphs and spreadsheets that will pop out from that analysis.
For the record, if I really wanted my preferred version of Leeds to Glasgow it would be in a Pullman dining car pulled by a handcar powered by Grayling, Rees-Mogg, Johnson and Gove in penance for the awful divisiveness they have brought upon this country for the amusement of their own egos.