Like I said,there's matter how you train your DMC but I prefer another way.I never use red arrows on DMC's but it's not mistake to use.Different styles,different managers.
By the way,I always use very motivated 4-5-1V with red arrows on MC's AML/AMR/DL/DR... Then I tried to put away the arrows of the MC's...But the most effective V style formation is without any arrows.I figured out this before two-three weeks.I always like to use arrows,but I figured out without any arrows is more effective.