Consider the example to define a PredifinedItenerary-Publiction containing a huge amount of Points. In the current DATEX-model, every single Point would be a "PredifinedLocation", i.e. every point is referenced with version and id. Obviously this is not what you want, and the maintenance of those refences might even result in performance problems. The same problem exists for NonOrderedLocationGroup. I can think of two solutions: Either to connect all three Predifined components directly to the Location component, or, event better, to reduce the Predifined components to just one component and connect it with the GroupOfLocations component. Please refer to the attached pdf for these tow proposals.
The issue sounds very reasonable. Yet, it would imply incompatibility with CEN/TS 16157-2 and is thus set to "needs work". It will be revised and taken into consideration for the next major release of DATEX II which will come along the CEN revision of CEN/TS 16157-2.
Resolved following agreed solution documented by Loic