I know the whole waiver/options thing can get confusing. Basically, once a player is placed on waivers and clears, he has cleared for the entire waiver period. For example, the Phillies placed Durbin on waivers after they claimed him, and he went unclaimed, thus, he “cleared” waivers. After a player clears waivers, he can be optioned up and down as many times as the team wants until the next waiver period. The current waiver period stretches from May 1 to July 31 at 4PM. The ambiguity here is, Durbin was placed on waivers before the May 1 start of the new period, so he’d have to clear again, which means they might not be able to send him down without getting claimed. Condrey, however, has been waived and cleared during this period, so he could be sent down.

That’s the rule, as I’ve read it in numerous places.