that is not illegal formation .
the formation you are saying is 5-2-2-1
DR--DC--DC--DC--DL
------MC---MC-----
AMR------------AML
--------ST---------
by the way you can also use 5-4-1 with your ml,mr and st red arrows . red arrows only on ST for this 5-2-2-1 ,to give him more 1 on 1 chance.