Also, you can tell the writers only half understood or just abandoned the Azor Azhai thing halfway. Drogon should have bowed to Jon. In that scene, Jon became Azor Azhai, he killed the one he loved in order to crystallize the power needed to defeat the Others.
And that power should have been the Dragons. While Martin talks about scouring the shire, I wonder if the original story was supposed to be Jon helping Dany in King's Landing first in order to secure her aid to go north. They win, but Dany suffers major losses. She still goes north, as per the deal--but then the Golden Company swoop's in and occupy King's Landing. The people, angry at the losses during the battle, pledge to the false Targ and Dany loses it, turns her army around and burns King Landing down. Jon knows he needs the dragons, but sees Dany is insane and is going to burn out the rest of the lords who just betrayed her and so kills her, and is able to wrestle control of the dragons in order to go north and kill the Others.
Anyway, probably holes in the above. But its pretty clear at some point Martin is going to make Azor Azhai play out with Dany and Jon. That piece got into the writing, even if they fucked it up.