I don't think this L-class upgrade issue is that new. The old 800 mile upgrade certificates and One-Way Systemwide upgrades stated that they were valid on only certain fares. Whenever I tried to use them they were only good on K class or higher fares. Usually I fly internationally and buy M class or B class fares and then upgrade with certificates domestically or us Systemwide upgrades. I agree though that sometimes the difference between L class and the next available fare can be double. In Feb I flew to Zurich and the L class was $500 and the next available fare was B class at $900. I took the L class and made sure I was on Swiss Air internationally. Also if you fly Eastcost to Hawaii, sometimes it is cheaper to fly Eastcost to Seoul round trip with a stopover in Hawaii then buying a domestic ticket.