Change of Gauge has always annoyed me and I am surprised there have not been legal challenges to its "direct flight (but see footnote)" approach.
I took this up with the EU Commissioner for Transportation after having an exceptionally bad experience with Iberia (bad even by their standards) when we flew from BCN to JNB on a COG flight. We knew it involved a change of a/c in MAD but we did not expect to miss our long haul connection, our luggage to go missing, and to be treated like dirt for daring to complain. I also did not expect to have to be a translator because the Iberia/AENA staff were too ignorant, lazy, and monoglot to make the announcement about the delays in any language other than Spanish. When I told them that the announcements should be in English as 50% of the passengers were English speaking, I was told that they must be 'idiots'. Idiots indeed, to be travelling with such a diabolical airline.
Anyway back to the EU, I received a letter stating that the practice was legal. However the CRS code of conduct makes the COG flights display in a lower position than nonstops or genuine directs.