In addition to mangling trees, I enjoy beating dead horses. What will be of this tree will be, but I'm not sure what I've learned here. And I'm here for no reason other than to learn.
Attached are before and after pics of the trunk chop. As you can see, nothing grew on much of the trunk and so I cut it down to the highest branch. Although I have a great to learn about sap flow and the like, "flow" indicates a back and forth. And if there is no growth in much of the trunk, then there is no "forth" and therefore no "flow" of sap there. Accordingly, I do not understand how cutting off what presumably was a dead portion of the trunk interrupts nonexistent sap flow. That is, unless the assumption is that buds popping higher up was still a possibility. All I can say to this is that I have a number of threads involving trees that had a blind reduction and which only grew lower buds. I was advised repeatedly not to expect any higher buds as the upper portions of those trunks were likely dead (and in fact no higher buds have grown on any of them). So my working assumption here was that much of the trunk could safely be removed.
In addition, as I basically left all growth intact (except for what was lost due to friction from the back of the saw), I don't understand how the tree is in any different position now in respect of existing growth to encourage sap flow than it was before the cut. Both before and after the cut the tree is in the position of needing to grow shoots in the lower portion of the trunk where sap is presumably still flowing (if not, the tree was screwed already). I viewed this as cutting now gets rid of what's not needed and allows the healing process to start.
Trees are resilient; egos not so much. So I'll say that I'm not arguing with anyone and just trying to figure this stuff out.