While identifying "control" questions is the most difficult part of employing polygraph countermeasures, it is not particularly difficult.

To the best of my knowledge, no revolutionary breakthrough in "control" question construction has appeared in the polygraph literature. However, some polygraphers may employ the less common relevant/irrlevant (R/I) technique, regarding which I recommend you see Chapter 7 of the 2nd edition of David T. Lykken's book, A Tremor in the Blood: Uses and Abuses of the Lie Detector (Plenum Trade, 1998). We did a poor job of covering the R/I technique in The Lie Behind the Lie Detector, and deficiencies in that regard will be rectified in the 2nd edition, work on which is in progress.