They can suck all day. If you're liked by the "Clique" at CBS you can suck suck suck forever or until the "Sale" comes ;D
On oldies research. I find it more helpful when to DROP a song than how many or what songs to play. Any experienced pd will know what the top testing songs are and yes it's usually between 300-500 songs.
Besides, in the very beginning SOMEONE at SOMETIME had to submit THEIR list to the focus groups. For instance people like Bill Drake, Bob Hamilton, Paul Drew, Mike Joseph, Scott Shannon, E. Alvin Davis, etc. These guys all claimed to have the BEST list. To this day they and others and their list vary as well as the number of songs.
5 years ago i tested 750 songs with 150 people. The next night we did another test with the same songs but with a different 150 people. Guess what? Entirely different outcomes!! Go figure. Research is a wonderful tool but to use it 100% for your decisions is foolish at best. You would be suprised at how many songs don't get tested that should be tested, but most in radio blindly follow the leader even in "unique Markets".. I remember working for someone at a CHR in the 80's/early 90's and he kept testing rock songs like Fleetwood mack, 38 special, foreighner. Finally he wised up and tested Madonna, Janet Jackson, Prince, Wham and those songs beat the ------ out of his outdated rock songs.
Don't let some of these "experts" on here fool you. Most pd's will put songs on the air they think is familiar at one time or another.