So did you read my entire statement or just a sentence then quote it??..
and yes, air shocks can and have been used as an effective way to add payload capacity, there are several kits on the market that do just that, not to mention a bevy of mass produced units that have a form of air shock on the rear for the self leveling style suspensions, like what came factory on my wifes buick, and countless other GM cars. I also said that in his application it was not the ideal answer but would work. I then told him his best bet was to have a set of custom coil springs made. repeatedly.