With my Tern Verge, I disassemble the bike quite a bit. It's total overkill, but knowing how rough baggage handlers are, I don't want to risk arriving with a damaged bike.

Generally, here's what I take off: chain, rear derailleur with hangar, handlepost, handlebars, seat/seatpost, one of the V-brake calipers, pedals (but they're QR so that doesn't really count), fenders get zip tied around wheels.

Then I wrap everything in foam/bubble wrap, including the frame & fork. I have a 1/2" layer of foam on the inside of the suitcase and I also put a crush protector in the middle of it.

It is a very lengthy and tedious process. I give myself about half a day to do it. I dread it actually, but I can't risk any damage in transit. If there was a comparable bike that I could simply fold up and put in a suitcase without having to go through this process, I would probably jump on it. Supposedly the Helix but...