I'm puzzled that the researchers were surprised. The type of exercise they looked at is exactly that which anyone who has read the literature on HIIT or SIT knows doesn't work:

http://www.exrx.net/FatLoss/HIITvsET.html

After a 5 week conditioning period on a recumbent cycle, The High Intensity Interval Training (HIIT) group perform sprints while the Endurance Training (ET) group performed a more traditional aerobic protocol, throughout the remaining 15 weeks. Both groups progressed in intensity. At the conclusion of the study, the HIIT group lost over 3 times as much subcutaneous fat as the ET group despite expending less than half as many calories. For every calorie expended during HIIT, there was a nine fold loss of subcutaneous body fat, as compared to the ET group.

I prefer the slightly different SIT protocol - it tore fat off me in a couple of weeks of beach running and I'll be using it with my new singlespeed. (In fact I designed the bike partly around what I need for the program.) The downside is that these are hard programs to follow - quality of training is the key, you have to keep pushing as you improve, and you will ache on recovery days.