Okay, it does there, but I refer to this part:

At this point, the pure wind force has fallen to 0, because the cart isn't moving relative to the wind. But the propellor is still producing a force dependent on G, A, and r.

So for the right values of G, A, and r, you'll still be accelerating.

This seems to equivocate between wind/propellor force and net force.