Forgive my attitude from earlier, but I stand by what I said. Adanorcil makes a compelling case so what are your thoughts on what he had to say? Seeing as how you still have your doubts.
Adanorcil's post was indeed a breath of fresh air.
Previously what I understood people to be saying was that Lorkhan and Akatosh were one single entity that was using both names. This is what I disagreed with. (In fact I am sure some people still think this)
His post clarified that Lorkhan and Akatosh do have separate identities. They are identical twins, who can swap roles and functions with each other, but still separate. This explanation makes more sense. The lore starts to add up.
You asked about my questions...well there are still some, particularly with respect to Tiber Septim.
They say Tiber 'Mantled' Lorkhan and became a divine. A divine responsible for War and Governance. However Lorkhan is the Space god (in opposition to his twin who is the god of time) If you Mantle a god, the god will walk like you and vice versa.
So why isn't Lorkhan changed by the mantling? Or conversely how did Tiber Septim become the god of war and governance when the deity he mantled was in charge of space?
...Just so you know, some people are saying Tiber Septim is Lorkhan and is also Akatosh, and they are serious about this. So Duality goes out the window and Akatosh becomes Okurin Meta (Three in One)....which in turn opens a bigger can of worms about how many other Et Ada have three aspects...