huh I find this totally incomprehensible. Is this easier to read if you spend a lot of time looking at wiring diagrams?

As someone who spends a lot of time looking at wiring diagrams: not really.

I think the concept of the map is neat (the arrival/departure times let you plan transfers!), but it is way too busy to be practical. It has at the same time too many details to give you a high-level overview, and not enough details for trip planning.

For a general idea a map like [0] would be better: it shows the stations and track layouts, so it gives you a general feeling of where to go. Want to go from Utrecht to Zutphen? You'll have to go either over Arnhem or Amersfoort. Want to go from Amsterdam to Groningen, but there are issues in Zwolle? Yeah, you're screwed.

For planning purposes a map like [1] is better: it shows you the actual services being run, with a vague indication of their frequency. It tells you that an issue in Alphen isn't a big issue for your journey from Utrecht to Leiden, as there are six trains an hour going Utrecht-Schiphol-Leiden. Want to go from Utrecht to Amsterdam? Don't bother planning, there are trains every 5 minutes. Want to go from Den Haag to Groningen? A direct connection is possible - but only once an hour, so don't be late or you risk having to transfer in Zwolle!

But honestly? They are more for nerds than practical use. Transit planner apps are far easier to use, will be more accurate, and provide exactly the information which is relevant to your journey.

[0]: https://i.pinimg.com/originals/0e/f9/2b/0ef92b7c4f2cf4d1b0c1...

[1]: https://nieuws.ns.nl/download/c10b58e3-54fc-4577-bf95-931b03...

It's a technical diagram - it's really not supposed to be that comprehensible, but more of a reference. The passenger-facing publications use regular timetable layouts.

Is it? What problems do you face?