I don't know if it's worth going through the figures individually, they are very similar to those from Axen and Axen which produced a series of posts a few years ago, except that the feature of COMPLETE reversal of insulin resistance is, here, presented right up front in Figure 6 and in the abstract too:

That figure for insulin looks a little dubious at 120 minutes but I'll let that go, I guess p was still > than 0.05... Pretty close to full reversal.
It's quite hard to know exactly how much this group understand about their results. They give roughly equal weight to the adverse (sic) effects of a ketogenic diet as they do to the fact it is reversible within a week (or less, they only checked at a week) of re-introducing carbohydrate.
What they seem to lack is the concept that rats fed a very restricted carbohydrate diet MUST be insulin resistant to survive, as happens in starvation. But maybe they are creeping towards some sort of understanding. It's about time. Good.
When people cite Axen and Axen to prove ketogenic diets are going to make you diabetic (there are folks who believe this, or at least wish you to believe it!) you have an answer in Kinzig et al 2010.
BTW, the links which led me here relate to using ketogenic diets to control both pain and inflammation. This is a potentially very useful tool but the beneficial effect does appear to be as rapidly reversible as the physiological insulin resistance... Ketogenic diets are a fix, not a cure (in the short term anyway). But inflammation appears to be a feature of ageing, long term, and if KDs work in "ageing inflammation" all we have to decide is the age at which we should all start on a KD. Unless someone has a method of stopping the ageing process of course....
Peter