The result of this was that Table 5 remained a mystery (though it was known to depend on past weather), only one dimension was known of Tables 7 and 9, and the finer distinctions in Tables 6 and 12 entirely lost. Cribs from Archery based on any of these tables naturally involved ambiguities and single letter equivalents could only be found for Position, Pressure, Present Weather (in most cases), Wind, Strength, Swell, and Temperature. The position was worsened after March 28th when Archery position trigrams were doubly cyphered and rarely broken. There was a slight compensation for this when 3 letter signatures were introduced on June 30th.
These shortcomings would not have prevented WWs from regaining their preeminence if the indicator tables had not changed monthly. As it was WW menus and Short Signal menus with WW links were used sometimes towards the end of months when the indicator tables were fairly complete; there was however an average of only one Shark WW a day in June and only about 3 WWs in the whole of August, though after this there was a slight recovery.
After 31.12.43 when 3 boats were kept in the Atlantic to send WWs twice a day every day, WWs became more useful for menus or paired days, but by this time Biscay Weather was in its prime.
The 3rd edition of the WW book was captured in June 1944.
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