Sometimes grafting is just because it can be high percentage vs rooting a cutting. Then you want to AL it off so it can be its own tree.I thought the purpose of grafting is to put a slow growing variety on a rigorous rootstock. Would air layering just the scion defeat that purpose.
What happened to you is why I don’t do grafting.All our in ground trees froze to the ground 14 miles from the Gulf. 85 degree days for 3 weeks then a freeze kills the part of the tree out of the ground. True to variety roots is the only way for us to grow lately.
I graft Pears, Persimmons, Pecans, Apples, and Citrus. Air layering almost everything else. I'm discovering ways to Air Layer Plums, Plurreys, Peaches, etc to get them on their own roots.What happened to you is why I don’t do grafting.