Yes, the ground test stands are at the UTC test facility near Jupiter, and it is definitely humid, but not like the UAE. I'm also betting the air salinity is playing a part.
No, the Mad Dog 80/DC 9 flys by the servo tabs. You won't get control surface movement without airflow.
Good point. I was initially thinking like the A380 where gates would need to be redesigned (which would never happen for a MOM) but you could just as easily put the stairs inside the airplane and...
Apparently by largest they mean dimensionally. By that standard, I guess the 777-9X is now the largest aircraft to come out of Boeing.
One look at an AOA gauge/indicator would prevent this.