FX Impact decocking

I was reading my Impact manual regarding decocking procedure before making adjustments on the knobs (Crown too). They say with no pellet in gun to bring lever all the way back, pull trigger and hold it back continuously and then bring cocking lever forward.
Would the same thing be achieved by bringing cocking lever back, remove magazine and then cock it and dry
fire? Seems like it would but I don’t know the internals and how that might be different than their procedure.
Randy