By Michael Guerin Bad news for New Zealand’s best trotting fillies comes as a bonus for the boys heading to Friday’s $200,000 NZ Trotting Derby at Addington. Because trainer Jess Tubbs has decided to target the Oaks with last Friday’s $500,000 Ascent winner Tracy The Jet. The outstanding filly made a mess of her rivals of both sexes when leading throughout in Friday’s slot race and is the TAB Futures favourite for both the Trotting Oaks and Derby back at Addington this Friday. But Tubbs says Tracy The Jet will…