Culbertson/Goren consensus (four-card majors, strong notrump, strong two-bids, two-over-one showing only about 10 HCP) began to fall apart during the 1950s and 1960s. The experts' answers became influenced less by judgment and more by system, some experts even abstaining on occasion because they could not use a favored treatment. When different experts preferred different systems it became difficult to reach consensus and the comments became less valuable. Therefore, in 1967 Kaplan and Rubens instituted a poll of experts to determine their bidding preferences (e.g., four-card or five-card majors, strong or weak two-bids, doubles of overcalls negative or for penalty, limit or forcing jump raises, etc.). Solvers were also invited to participate in the poll, but their role was restricted to breaking ties among the experts. The result was Bridge World Standard 1968, now known as BWS 68. There have been three major revisions of the system, in 1984, 1994, 2001, and 2017. BWS has always been intended as a platform for answering MSC problems, but also as a system that two experienced players could use if they had never partnered one another. Another use for BWS, perhaps intended in 1967 but never touted as a rationale, is to provide a means of tracking how expert preferences have changed over the years. TBW regards the MSC as its most successful feature; certainly it is its longest running. It has been imitated in one guise or another by most bridge periodicals. Several sample MSC problems, answers, and commentary can be found at TBW's web site. Challenge the Champs Challenge the Champs (CTC) is, in the words of TBW, "… a continuing bidding battle. Each month, two leading pairs compete, bidding deals from actual play (taken from old tournament reports or submitted by readers)." CTC is a feature that debuted in The Bridge Journal, a periodical edited by Jeff Rubens which was discontinued when Rubens joined the staff of TBW. At that point TBW took over the operation and the publication of CTC. The format is to give each pair ten hands to bid, just as though they were at the table. Awards for different contracts are pre-set, and the results are scored as though they were matchpoints awarded on a 12 top. Over ten hands (again quoting from TBW): "… in the fifties is over average, in the sixties might win, higher is phenomenal." In its original form, a pair would continue