OK - well according to wikipedia, it is the former motto, and whether you state it's 'lack of counsel' or 'deception' as the translation, the English translation of 'deception' has been used as the title of a book, as used by a former Mossad agent, to validate the understood meaning of the motto by a former Mossad agent himself.
According to modern Hebrew speakers, the way that the word "Takhbulot" is translated in the modern age is that of 'tricks, ruses, ploys (i.e. deception) different to that of the 'wise counsel' which is a translation from the King James bible, and different to the translation in the modern Hebrew.
"Quote:The solution is written in the Bible (Proverbs 24:6): “For by ruses thou shalt make thy war.”
(In the King James version, the Hebrew word Takhbulot is translated as “wise counsel”. In Modern Hebrew it means ruses, tricks, ploys – and that is the way it is understood by all Hebrew-speakers today.)"
Now the motto has been changed to another similar phrase from the same biblical passage of proverbs:
Mossad's former motto, be-tachbūlōt ta`aseh lekhā milchāmāh (Hebrew: בתחבולות תעשה לך מלחמה) is a quote from the Bible (Proverbs 24:6): "For by wise guidance you can wage your war" (NRSV). The motto was later changed to another Proverbs passage: be-'éyn tachbūlōt yippol `ām; ū-teshū`āh be-rov yō'éts (Hebrew: באין תחבולות יפול עם, ותשועה ברוב יועץ, Proverbs 11:14). This is translated by NRSV as: "Where there is no guidance, a nation falls, but in an abundance of counselors there is safety."