Treat emissions on air routes to developing countries differently?

On 18 May 2009 GreenAir Online carried a very interesting article by Chris Lyle, formerly with ICAO but now Chief Executive of Air Transport Economics and an adviser to the UN World Tourism Organization. He suggests that if the principle of Common But Differentiated Responsibilities (CBDR) is to be applied to international aviation it should be based on air routes rather than the status of an airline's home country.

What Lyle proposes would partially solve the problem that Australasian airlines, such as Qantas and Air New Zealand, would face if emissions from major competing airlines such Emirates, Singapore Airlines and Cathay Pacific were treated differently because they come from "developing" countries.