I've read that too. It appears to be a combination of both strengthening and CoG... but honestly, it can't be more than 100lbs lighter than the A-5... 6.1inches? You could take a dump in the rear of a plane and have to lengthen the nose by 6.1inches.
Besides that, I wouldn't look for any European air craft being modelled in 1.10... it's an early war pacific update as near as I can tell.
While the A-3 might be neat... probably just because of an updated look, the difference between it and the A-5 in terms of manuverability and visual differences is close to 0.0000005%...
in other words, substitute the A-5 with the A-3 and you've got yourself a 100lb heavier A-3. (if even that much)
Here, found weight for the A-3: Loaded 3,977 kg
A-5 loaded: 4,000kg...
How much is 33kg in pounds? EDIT: 72.6 pounds difference.
-SW