Hi Al,
I remove the pedals, turn the steering 90°, remove the air of tyres, barrs off, light off and put the bike in transparent plastic bag. I take care that the bike is rolling and nobody has to carry the bike. Important is that your confirmation contains the size how big your bike can be.
That's it. I made the best experiences with this kind of packing - and I don't care about scrateches
Sometimes you are force to use a bike carton. Several times I received only parts of carton and the bike. I friend of mine didn't used the plastic and had dints in his frame.
I think British Airways forced me to use a bike box - but I can't remember it was 10 years ago.
Travelling with bikes is nowadays very convinient. 10 years ago it was really funny. 4 hours for Check-in, estimated costs of 1000 EUR (one way) that was a lot of negociation at the airport. Today you pay bike tarif (80-100 EUR) one way and that's it.
Thomas