Was having an interesting discussion about the seal and the cab aperture (opening) relation to the box aperture.
The motorhome spends 99% of its time parked. The function of the seal is to join two compartments that at times have a dynamic relationship (they move with respect to one another).
My measurements show our cab when aired up is 1.75" higher than when deflated.
Ignoring side to side movement for a moment, most of the cab movement when aired up is in the down direction.
The question is, would you set the two apertures aligned with each other at rest deflated or aired up?
Keep in mind the purpose is to seal & join two compartments, while underway there would be minimal traffic between the to compartments, most traffic would be when parked and deflated.
Now, mechanics of this would say when underway you'd want as close to a neutral alignment to allow for the greatest movement between the two, yet when parked (all weather conditions) you would not want it to be under stress.
Further consideration is this passage way is going to be small; about 30 wide by 59 tall so misalignment while parked means this would be further reduced in height when it would get most of its use. Other side of the coin is while underway you wouldn't want a smaller tunnel either?
In the end it really comes down to aesthetics; I'd prefer it were lined up instead of like a train tunnel started from both ends at once and not meeting in the middle.