shortens reach but not the toptube length since the sta slackens as well. but yes, shorter reach, longer toptube for seated position riding which is what I'm more concerned about. I'm riding a M hightower V3 which is longer than the previous V2 I had, the hackler now is even longer... getting close to the limit but if I would to size down to a small it's definitely gonna feel too cramped for me10 mm longer fork slackens hta by about 0.5° and shortens reach. Stem is coming closer to you. Think about it