What was great about the Fertile Crescent? How does this support Diamond's idea of geographic luck?

Jared Diamond discusses several different advantages possessed by the Fertile Crescent that made the early development of agriculture possible there.
One was its climate, which featured long, dry summers and mild winters with plenty of rain. Basically, this climate is highly conducive to cereals that were the basis of early agriculture.
Second, most of the crops, like wheat and barley, that were cultivated by early agriculturalists are native to the region.
Another advantage is that many of the native crops to the region are easy to cross-pollinate, and therefore they are conducive to the kind of selective agriculture that produces high-yield crops.
It was also the largest Mediterranean climatic region, which meant that its crops could be grown over a large region, enabling genetic diversity.
It also had a wide variety of domesticable large animals, like goats, sheep, swine, and cattle.
Finally, Diamond argues that the relatively small coastline of the region meant that the agricultural lifestyle faced little competition.
For all these reasons, agriculture developed earlier in the Fertile Crescent than elsewhere. This fits into Diamond's thesis because he argues that the development of the things that made Eurasian conquest of the world possible—guns, germs, and steel—all proceeded from the development of sedentary agriculture. This was not because of any cultural factors, he claims, but just because the location and the climate made such agricultural practices possible there and not necessarily elsewhere. In other words, the Fertile Crescent's ability to thrive was an accident of geography.