I have used many methods, and they all worked. Some had higher success than others. In the end, it comes down to balancing the various parameters of each technique. I Louisiana where the humidity is high, maintaining humidity outside isn't an issue, so rooting outside is much easier. During dry winter weather, and generally dry weather all year long, in California, providing an enclosure to maintain humidity is a must in most cases. Almost any rooting media works as long as you control moisture levels appropriately. But some media are more finicky, and make that control harder. In France, sometimes they take a 2" diameter branch, about 5' long, bury 3' in the place that they want the tree in the orchard - they root the whole orchard in place. We tend to grow them in pots from smaller cuttings, and transplant when they are larger.