There's a bit before that that says that the times that the temperature limit is hit are those times there is minimal airflow. When the user hesitates in mid-draw and at the beginning and end of the draw.
So during normal use you are not getting to the temperature limit unless the airflow or wicking is sub-optimal, no matter what the temperature limit is (above 390F). Setting maximum watts will mean the vape is largely uncontrolled.
I would love to see the patent that John refers to. Unfortunately it hasn't made it to USPTO.gov or Google Patents yet.
It seems to me that the picture is still not complete. After all, if we never reach any temperature over 390F, then the temperature setting cannot affect the taste. I can only think that we rely on the sub-optimal wicks, the hesitations and end-effects to push the atomiser into a controlled dry-burn in order to modulate the taste. The DNA40 controls this process so we can tune the effect to taste without the danger of going too far and getting those 1200F coils which Evolv observed and which may release nasty products.
So, contrary to what we have been saying all along, watts and temperature are indeed two different variables, because they operate at different times. Watts controls the vape while the wick is efficient and airflow is adequate, and temperature controls it when those fail. Contrary to our expectations, that is not a rare failure case, but a constant and required part of every draw.