The presence or absence of a Ten in a long suit should very often make the difference between bidding and passing in an overcalling situation (bidding after the opponents have opened). See The Rule of Ten.
East Deals None Vul
South’s 1 overcall – winning bridge in spite of the paucity of points – made reaching the excellent 4 contract very easy. Knowing his partner had five decent s and an absolute minimum of 6 points, North saw no reason to mess about (if playing the Unassuming Cue Bid, North could bid 2 to show 10+ points and a fit).
West led 2 to dummy’s A. Declarer correctly resisted the temptation to draw trumps, rather playing A, 5 to K and a third . West won 10 and led J, East overtaking with Q and leadingK, South trumping. South trumped 4 with dummy’s 10 (an extra trick he would not have made if he had drawn trumps earlier) and held his losses to A and a trick in each minor.
THE RULE OF TEN (THE SUIT QUALITY OVERCALL TEST): Only overcall when the number of cards in your suit (minimum length five) added to the number of honours (counting one for each honour – and including the Ten) is at least as many as the number of tricks you’re bidding for.