As a handling guru, let me weigh in on rear sway bars.
Off-roaders like to take them off or disconnect them temporarily. But for 100% street driving, and especially cornering, I would not recommend disconnecting the rear bar unless one continues to drive at way below the limits of the vehicle.
The 360 platform was specifically designed to address the problem of high center-of-gravity on SUVs. (Remember the Ford Explorer fiasco, and the potential rollover issues with the Suzuki Samurai and Consumers Report magazine that ended up getting settled out of court.) Roll was designed to be less than 3 degrees in high-speed cornering, and they did some innovative work on the design, including mounting the engine so low that the front driveshaft goes through the oil pan.
The rear bar is an important component to that high-speed handling. If the bar is stiffened (such as with an aftermarket bar such as the Hotchkis) it changes the handling balance by reducing the built-in understeer and causes the truck to corner more neutral. This is the goal for experienced drivers.
I spend a lot of time on race tracks, and trust me, the Trailblazer platform does an amazing job on the track for a mid-size SUV. It handles very neutrally for its size. (I have a Hotchkis bar installed.)
Here in Canada, it also helps cornering at even slow speeds in icy conditions.
If you know what you are doing, one can really use a stiffer rear bar to tweak the handling. GM never designed the 360 platform as a police vehicle, but they very unofficially sold it to a lot of police agencies as an undercover and stolen auto unit vehicle, mostly because it is a) ubiquitous; b) has a tough frame for ramming if necessary; and c) goes like stink when it needs to.
But by removing the rear bar on the street entirely, it changes the handling balance toward understeer. No big deal if it is your grandmother getting groceries, but if you like to drive and want good handling, it is going to plow in corners a lot more.
GM knows handling. I learned that very early on when I started making part of what my wife laughingly refers to as a "career" by testing and writing about police vehicles. In fact, I once wrote about the difference between understeer and oversteer in handling dynamics. "Understeer is when the driver is scared. Oversteer is when the passenger is scared."
When we set up race cars for the track, to reduce understeer, we stiffen the rear suspension. To reduce oversteer, we stiffen the front suspension. (This is why one can see photos of properly set-up FWD race cars going around a corner with their inside rear tire literally off the ground, and rear-engined cars like 911s with the inside front tire in the air.)
My two cents. (About .6 cents U.S.) If off-roading is the main focus, disconnect the rear bar. If good handling on the street is important, keep it connected. If better handling than stock is a goal, look at a stiffer aftermarket bar like the Hotchkis.