GM actually had the right idea with it, as GMC was the one that wanted it to be available for it's Towing Consumers.... Basically they thought that it was something that was needed by those individuals that were towing large loads, such as those with Large Fifth Wheels,Car/Truck/Motor Sport Transports, or even larger Boats/Heavy Duty Equipment trailers....
The Trucks were quite capable of handling their intended loads, but the majority of Target Consumers just didn't have full interest in having an Expensive Option, that they just weren't comfortable with it's Handling Characteristics....
For Civilian Personal use, the Trucks Basically Bombed in the Showrooms, but for Commercial/Heavy Duty/Fleet/Military use, the trucks actually still have a decent market presence...