Probably one of the major reasons the "traditional" SAT/Achievement tests were replaced in the mid-90's by the SAT I and II. The scores were also "recentered" with the old average of 900 Math/Verbal now about a 1000. Then they threw a third score on it a few years back so a perfect score is now 2400. I took it in 1983 and got around a 1400 combined on it (IIRC, 760 Math, 630 or 640 Verbal.) I was also applying to some higher-tier schools so I took English Comp, Math II, and Physics on the Achievement Tests. I did okay on those, but the one thing I remember is there was one kid who had a hell of a runny nose who kept sniffing (loudly) through the entire thing.
By the end of that morning the entire room was ready to kill that kid.