I haven't quite got my head around the concept, but the proposal seems to be for a single train-pair (excuse the Germanism) on each route covering the maximum possible distance in a day.
That's strangely out of line with mainland European practice these days which is based on relatively frequent (2 hourly) services over the whole day, with trains berthing overnight at intermediate main stations (Hamburg-Budapest now has only one daily train, but a 2-hourly service is provided with sets originating at Barlin, Dresden, Prague, Brno and Bratislava (from memory which may be slightly out of date, but you get the idea); internal German and Polish routes work the same way.
The idea of defining the long-distance corridors is fine, but I can't see - for example - Stockholm-Bremen passengers being excited at an 0600-1400 trip just because the train needs to reach Paris for dinner!
Each of these routes serves a whole load of overlapping markets, and I doubt that many of the really long-distance flows have sufficient numbers to warrant running a train for them. Far better to run multiple trains, even if they make more stops.
(With night trains that's less easy, but they are on another thread!)
A minor but related point - the authors are focussed on end-to-end times at the expense of major intermediate stops: I noticed stops at Lyon St-Euxpery (airport) not Part-Dieu and Arth-Goldau not Zürich or Luzern for example.