I think it is also important to note that what matters, is how much hair we are left with as we continue to progress in hair loss. When moving a large amount of FUE, you are inevitably extracting from a larger area and consequently an area that is not as DHT resistant. When you start with FUT, you minimize this greatly which allows you to utilize that 'sweet spot' of DHT resistant hair. Then you can move over to FUE as the adjunct procedure.
The other factors you mention about the skin stretching and the change in direction are interesting and i look forward to Dr Bisanga answering them.
Doctors like Dr Konior and Dr Wong say that combining both maximizes lifetime graft potential. It would be great if they could answer your list of questions as well.