Pet clutch skids on the leading shaft to rotate with it. Many of the equipment around the layshaft is fastened with it.  Once the still left-hand Pet clutch is introduced to skid for the left with the gearshift lever, it messes with the clutch equipment, as well as higher-speed equipment https://gearbox-auto19630.blogtov.com/14286110/helping-the-others-realize-the-advantages-of-gearbox-auto