WHY would you put the set screws in a location where they can hit the adjuster?If you follow the instructions and do them up properly they dont hit the adjuster.
depending on the positioning your set screws they can be covered up which means you have to lower the adjuster to even be able to remove your armThat’s to accommodate a large variation between turntables in the height of the platter surface relative to the armboard.
You want to set the postion of the pillar shaft such that the arm is parallel to the record when the VTA adjustment is dead centre with the cartridge mounted - this gives you the maximum VTA +- adjustment.