I have the 1982 "Era V Audio Obstacle Course" record, also known as the TTR [Trackability Test Record] -117. The two are the same.
Though modulation level does affect skating force, the really important reason to use the modulated test grooves is that they let you hear when you have your antiskate set correctly (with a silent groove or a blank (ungrooved) disc, how would you really know?). You don't need an official test record; you could simply use any unworn record with centered sounds (vocals are usually centered) that are difficult to track and adjust your antiskate until the distortion is equal in the left and right channels. Using a test record gets the job done simpler and quicker.
Remember, there's no one antiskate setting that's absolutely correct for every record, every stylus shape and every tracking force. As I said, it's a compromise.