Ovation airs So You Think You Can Dance reruns. As in, they run them for what seems like 24/7 from Friday-Monday, or at least they did some time ago. My wife started watching that show this year and has tuned into the Ovation reruns to see routines from past seasons. SYTYCD brings back all-stars as well and she says that looks for the all-stars when they were past contestants.
How is she on recognizing the SYTYCD finalists that have appeared on
Glee? (In the current storyline, the school's "other show choir", The TroubleTones, has Comfort Fedoke and Jaimie Goodwin - excuse me, "Season 4's Comfort and Season 3's Jaimie" (seriously, the only former contestant referred to by first and last name is Chelsea Hightower, and I have a feeling it's because the producers of Dancing With The Stars made it a condition for them even allowing her to appear as an All-Star last season) as two of the nameless (and uncredited) background singers (although they usually have the dancers just lip-sync to unshown, and equally uncredited, backup singers).)
My take on this is that GSN must have forgotten about "The Amazing Race" fiasco a few years back.
The difference:
DWTS = celebrities
TAR = "Who's that?" (Seriously, name anybody who has been on TAR who wasn't already famous before their appearance)