My guess is the high-fat diet might work for females, too, if the diet is high enough in fat and the event is long and slow enough to make a difference to fuel use. The findings need to be confirmed with a bigger sample size, of course, and there may be individual differences in the response to different diets. For various reasons the final enhancement is likely to be 2-3 times greater. Stick to 4-min intervals until more research is done. So don't start training with an oxygen mask yet.
Real competitions are the most valid but are impractical for most well-controlled studies.
Some tests may be more reliable than real competitions, but a change in performance in such a test may not mirror a change in a competition. Stephen Seiler has since pointed out that the power developed in rowing and on the ergometer is proportional to the cube of the speed, so percent variations in time to complete 2000 m translate into bigger percent variations in power. This argument applies to all wind-braked ergometers like the Concept II and Kingcycle, but not to treadmills or electrically braked ergometers. We're now doing a big rethink on the relative reliabilities of ergometer-based lab tests.