What's the best score, with the worst dancer(s) gethin jones/kenny logan?
CREATE TABLE "highest_and_lowest_scoring_performances" (
  "dance" text,
  "best_dancer_s" text,
  "best_score" real,
  "worst_dancer_s" text,
  "worst_score" real
);
SELECT "best_score" FROM "highest_and_lowest_scoring_performances" WHERE "worst_dancer_s"='gethin jones/kenny logan';