Your first sentence says it all...genetically predetermined...an overall yellow cast to a red maple in fall has more to do with the amount of pigments predisposed in the tree, over the year to year variances in water and temperature.
Walking fields of trees of specific cultivars, on different soil types will show some shades of variation as a whole, not individual yellows or oranges or reds as microenvironments.
The cultivared red maples are predisposed to having higher concentrations of sugar in the leaves that turns to anthocyanins that are the reds. These sugars are from the photosynthetic reactions...the cultivars have inherently a greater concentration of sugars that can turn to anthocyanins than a straight non-cultivar. In simple terms, the shortening days and cool nights of autumn trigger changes in the tree. One of these changes is the growth of a corky membrane between the branch and the leaf stem. This membrane interferes with the flow of nutrients into and out of the leaf. The sugars increase in the leaf, the chlorophyll production declines, the anthocyanins show through. The reds aren't washed out of the leaf by irrigation. The root loss by digging the tree exhibits itself as smaller leaf size and lesser amounts of leaf tissue overall...the chemical makeups and concentrations inside the leaf remain intact for the most part.
A smaller than normal leaf because of the stress from digging will exhibit the similar fall color of the tree leaf 2 years in the future as a larger leaf from a tree not under as much stress.
If all this wasn't true, why do we all pay extra money for the improved cultivars and not just play games with irrigation and NPK to get color. Remember trees produce their own food from elements (photosynthesis)...you can't give them sugar water and have the sugar go into their leaves...they manufacture it themselves.
A yellowy red maple will never show the brilliance of an Autumn Blaze cultivar even planted side by side, dug the same and even in the tight confines of a wholesale yard.
