Very interesting. I have crabapple trees that put up leafy shoots from roots, called water sprouts I believe, and these new treelings don't bloom like the other new branches on the flowering crab trees. Similarly, I've dug new sprouts from roots of rowan trees that have since grown into 10 ft-tall trees before they bloomed. I bet citrus trees grown from root cuttings revert back to low node count like seedlings.