I don't know where you got that impression.
Well, the four years that i owned the same year Trans Am is what gave me that impression. I noticed its an SS so its got a slightly different suspension than a stock Z28/TA, but i remember its cornering being alittle sub-par for a "sports car". Not saying it was bad, but i think the weight distribution wasnt ideal, definately wasnt a nimble car and you felt all its weight when driving. Perhaps the mods done to your SS have improved those issues, but if you ask me the LS handles way better than my TA did, the LS isnt as fast but drives better for sure.