Not so. Ancient Dragons will happily strafe you to death without ever landing. They can be a real, problem until you get a certain shout.
What difficulty are we playing where the Dragons are so easy? Perhaps turning it up would make the easy part go away.
Wrong. Every dragon has more or less the exact same Ai pattern. The only thing that alters whether a dragon lands or not has to do with positioning. If you are fighting a dragon in a location too small for it to land, it won't land. Every dragon fight, Aldion or otherwise boils down to:
1. take cover/interrupt shouting with clear skies
2. wait for it to land/dragonrend
3. Kill it with power attacks
4. If it lives and damages you , spam healing items ithout penalty
5. repeat from step 1