Now time to get the #BaleineBleueWeekend still even cheaper :

I figured out the pricing of  Deutschlandtarif is more than 3 times the traffic association fare in the train I booked in the afternoon.

Btw. the funny paper tickets with hand written notes are now also well prepared with a good old DB passenger rights form. DB will have fun with this hand-written notice in French 😅.

I find it surprising how you don't even need cross-border ticketing to get fare calculation impossible but a simple traffic association border is already fully sufficient.