I think both points make perfect sense and each theory is equally valid. I just happen to subscribe to mine.
While in your mind both points make perfect sense both can't be right, and for that matter neither might be. However of the scanty evidence that does exist i prefer my theory.
As a child Tut was easy to control, manipulate, lead but as he grew to maturity he began to realise the power he held and wanted to exercise it, possibly contrary to the wishes of Ay. Ay may have realised that his hold over Tut would not last the older Tut became so if he wanted to hold on to power Tut would have to go.
Again you are holding to 20th and 21st Common Era, understanding of "child rulers". Queen Victoria came to her throne at 18 and was controled first by her mother, an uncle, her government, then by her husband. There is no proof that any Egyptian Pharaoh (except Thutmosis III) was controled by anyone even if he came to the throne at a young age. It is an assumption based upon Western European history mostly.
How can you say "Well there was no proof of any kids or that they had intercourse so it didn't happen"?
If your going to quote me i would appreciate it, if you quoted me instead of implying what you think i said. The fact is neither Ay, nor Horemheb had children that succeeded them.
Look at the examples of other rulers: Napolean in his 13 years of marriage to Josephine could not father and heir. He was so desperate for one he divorced her and married the Arch Duchess of Austria. Another king, Henry VIII, was so desperate for heirs he divorced 2 wives and exected 2 more. The one who finaly gave him his longed for heir died soon after. Only one wife survived him. In over 38 years of marriage to different women he only managed to father one son, who wasn't even healthy and died in his teens.
My point in the above is maintained by yourself Kiya, men who rule are desperate to have an heir. However neither Ay, or Horemheb had a ruling queen while they ruled as Pharaoh. If either of them had a son by a minor wife why didn't that son come to the throne. By the way Joesphine was considered unfertile due to at least one abortion before her marriage to Napolean. Abortions in those days often left a woman unable to have futher children.
You say that it is not at all valid that Ankhensenamun's problems begetting an heir would not have carried over into any potential mariage with Ay. Well not only is it vaid but it is a very obvious point to speculate on, particularly as the mummified feotuses found in Tut's tomb showed evidence of a genetic disorder. If Ankhesenamun was indeed Ay's granddaughter trying to father a child with him would only compound and add to the problems of fathering an heir.
Again, you make a case for my position Kiya, if Tutankhamun was her half brother, uncle, or cousin and not her full brother. One would think the blood relationship would have been such that her children in Tutankhum's tomb might have been free of genetic disorders.
Think Kiya think please.