Throw /follow into the Melee Clones attack macro perhaps?
On the rare occasions that my sword rogue is part of my multibox party I have all of her attack macros use /follow within the attack macro itself. I also have my backwards key shared amongst my toons so what usually ends up happening is the tank is walking backwards past the mob and the rogue is generally in stabbing range and keeps moving towards the tank whenever she gets out of melee range...
/a focus
/follow focus
/startattack
/castsequence reset=target/combat/10 Sinister Strike, Sinister Strike, Sinister Strike, Eviscerate