It was explained to me that if you didn't fly enough to stay current, that they thought you needed a little more "review" in the sim that just a 3 and 3. Said something about an event that happened at UAL with an f/o that was always getting his 3 and 3 in the sim, and things went downhill fast when something went wrong on the plane one day.
I dunno, just passing along the rumor.