@JPB,
I think that's an unfounded assumption. There is no evidence that Got-Daffy is particularly militarily competent (in fact, the evidence is that he's rather militarily stupid, despite his education), but anyone operating in Libya knows that there is only the very short front in military operations. The rebels aren't going to be stretched out, because they don't have to occupy and hold large tracts of country. Fifty kilometers from the coast, there is nothing.
During the campaigns in North Africa in World War II, Rommel made use of this to do an end run around a rather weak British presence. But to do so, he had to cart all his food, water, fuel and ammo into the desert beyond the coast behind his forces, and although he made it all the way to Benghazi, his bolt was shot. He was unable to take Tobruk. It was another year until he had built up enough to renew the offensive and finally take Tobruk. From the point of view of both sides, it may well be a hard slog.
The only way to overcome the liability of the desert is through air power, which allows you to strike into your enemy's rear without actually marching there. Got-Daffy no longer has that card to play.