Well, its not all that difficult to understand.
1) JET A fuel is not rafined in Qatar. So although Qatar has a big oil reserve, it still has to ship the crude oil to somewhere else to get it converted to JETA after which it is being shipped back here. So all in all, it still is rather expensive, even for QR.
2) Imagine if QR could get that diesel-GTL fuel certified for airplanes! Not only could the whole QR fleet fly on this fuel, Qatar could sell this fuel as well as the copyright of the certification and procede al oover the world in view of the shortage of crude oil!
3) Guess which country is profiling itself as the largest producer of what they claim is the most environmental friendly fuel.....RIGHT! QATAR!
So if they ( QR and QATAR) can pull this one off, its a win win situation no mater how you look at it!
Qatar will just become even richer, and so will the illustreous AAB!!
Who says our creator ( whoever that may be...

) designed a fair and honest world....