Chelsea will never get Ribery, and Chelsea know that. This is all about putting pressure on Spurs, calling Levy's bluff once and for all. Chelsea are trying to say to Spurs "We want Modric, but we won't wait for ever/pay more than we've offered, we've got other targets". Spurs are playing hardball, so Chelsea are trying to match that.
Personally I think Spurs will force Modric to stay, at least until next Summer, and I think that will be a mistake. Modric couln't have made his feelings any clearer, he doesn't want to play for Spurs. He asked not to be selected for the City game, Redknapp forced him to play anyway, and he was a passenger/virtually invisible for 90 minutes. The Modric Spurs get this season will not be the same Modric they had last season. He doesn't want to be there, and that can only manifest itself negatively in his displays. He'll grow to resent Levy, and Spurs as a result, for preventing him from moving to Chelsea, especially on Tuesday or Wednesday nights when he watches Chelsea v Valencia prior to preparing for the big Spurs v Shamrock Rovers match on the Thursday.