I think you have been watching too many airbag buses and coaches...
The link i gave was for the picture not about the year,i couldnt be farked finding the excact one.

Just had a look at that bar your talking about if its the one just rear of the airbag conected to the chassis,thats the panhard bar connects to a plate that goes between the diff cover and the diff housing,cuz now we on airbags not springs we need something too stop the axle from farking off..
Watch this vid from 1.00 min too 1.50
YouTube - GM 2001-2010 2500,3500 HD 4-Link & Air Suspension Install

I dont think it'll be like driving a car with **** springs and no shocks,there's a vid on youtube showing handling with airbag suspension around cones and a race track,i remember when driving intersate me mates mack on airbag was rougher then mine with hendrickson spring **** end which gives me the opposite concern too yours.