I also remember seeing the trailblazer post but also remember someone saying that it is very un-safe to use it as a tie bar. The sub-frame brace would probably just scrap if your slammed. I'm no expert though.
It is a tiebar, similar in concept to what is used on the front end of the car to tie the lower points of the cradle to gether. The inherent flaw with using the trailblazer piece is that there is no swivel to the end so you actually improperly load the ends of the bar. You really need a Heim (or ball and socket) style end on the rod to make it work correctly, you want the dimension to remain fixed, but they ned to move through their arc coreclty and the trailblazer piece prevents this.
I had the trailblazer bar on my Addco rear bar for over a year... never had any problems.
3 years here on the eibach rear bar
cost- 8$. not sure the price now or the GM part #
i remember event telling us it will crack and absolutly need heim joints. i say the hell with that . why go through all the trouble and $ building one, when u can spend next to nothing and bolt it up and have the same results?