HMMM, without hurting everyones feelings, shortening the top link will for sure make it less agressive which is good for grading where you just want to spread loose material. Start to increase the length and it begins to get more agressive as the blade angle gets more toward vertical and as you keep increasing the length it will again start to become less agressive as the blade will again just scrap the ground and not cut in. A mid point between shortest and longest is the most agressive point on a blade or box blade. However when tilting the box blade forward(shortening the top link) the scarifiers will become lower. If you dont wish to scarify, then you have to raise the scarifiers if you tilt too much forward. I usually put my scarifier teeth almost level with the bottom edge, then I can shorten to scarify or lengthen a few rounds to pull dirt. Lengthen too much and it wont cut or pick up anything.
