Remember, your virutal pilot doesn't have his face right up next to the dashboard like you have yours up near your screen.
My virtual pilots head gets 2.5x bigger also, not just figuratively anymore considering this revelation. Not used to admitting that, but there you go.

Magnification in RL doesn't do what you are describing. I couldn't look down at my dash panel if I was looking through a scope. It would be blurry. My head and the dash panel also don't increase in size at a 1:1 nor would the reticle you see so clearly. This means little except that something is not a precise translation of zoom function; therefor something is not being included in the equations and the equations you are using probably only apply to real life..
All the math you have done still doesn't prove anything to me other than the virtual objects get 2.5x bigger, not that it is actually increasing the pilots vision 2.5x.
Tell me this, at what distance does AH model pilot furthest sighting of another aircraft? 8k for fighters? I don't remember. So when I hit max zoom can I see a fighter further than 8k out? I don't recall that happening.
At what distance can the pilot start to see details of the aircraft? And does zoom increase that distance?
I've seen no magnification happening and It still seems that if the gunsight increases in size at a 1:1 with an aircraft in sight, then everything else also increases, including the pilots head, at a 1:1. The only thing that changes is the amount of fine details.
If someone had the money for a 10' x 15' screen and a super graphics card that can render details so far buried in the coads of AH that they never see the light of day, ...then you would have actual 2.5 magnification.
I'm beggining to believe that the 2.5x you are getting in tanks is also just an illusion.