score:3
In case of control, a Passport or ID card will be needed to prove your identity.
Even if you don't need a passport for border checks within the Schengen area , it is still always highly recommended to take a passport or ID card with you, so you can prove your identity if needed (if stopped by police, boarding a plane, etc.
and
Driving licences, post, bank or tax cards are not accepted as valid travel documents or proof of identity.
Source: https://europa.eu/youreurope/citizens/travel/entry-exit/eu-citizen/index_en.htm
Upvote:6
So, after successfully having returned to Norway, I can answer my own question.
Is it possible to successfully perform this trip?: Yes
Is it legal to perform this trip?: Not really, as per the law you should always carry proof of citizenship.
Will anyone ask to look at ID during the trip?: Probably not. You will never cross any official passport checks, so the only things left would be some sort of a random spot check (I have never seen this happen) or a check at the gate (airline employee checking IDs as the flight is boarded - this happens randomly, and it is up to the airline employee to decide if to allow you on board or not if he is not satisfied).
I did not face any gate checks, and managed to do Oslo-Copenhagen, Copenhagen-Amsterdam (my original Oslo-Amsterdam flight was cancelled), and Amsterdam-Stavanger without ever being asked for ID. But for example, the flight before mine at the gate in Oslo, which was to Helsinki (Finland), was checking IDs, and a passenger was actually unable to board his flight because of some possible issue with whatever document he presented.
So in the end, I do not recommend attempting this. It will probably work in a pinch, but per the law, always carry proof of citizenship on you.