You do realize the epitome of modern soldiery is a soldier that can think for themselves and take initiative, right? The whole reason modern militaries have chains-of-command below the company level is due to increased need for small-tactics and flexibility. When the sergeant in command of the squad gets killed, you want a soldier to be able to stand up and take command of the squad, not just herp a derp under fire until another officer/NCO can take command.
This isn't the 1800's, where armies stood in blocks and blasted at each other.
Not to mention: orders aren't exactly spelled out with steps labelled. Even in small unit tactics, orders usually encapsulate ,' Hey, squad one, take that house!". Everything else is up to the soldiers in the unit. You want intelligent soldiers, capable of thinking for themselves, specifically so you don't have to hand-hold them through tasks. Hand-holding soldiers means more multi-tasking, meaning more complicated orders, meaning more things can go wrong
Stupid soldiers who stand around and wait for orders are the exact antithesis of modern (and future) warfare.
I do realize that. I also realize that the military is using robots. You know for menial or dangerous task. And what is a vat grown soldier, if not a biological robot?
Also, don't forget the Frankenstein syndrome
http://medical-dictionary.thefreedictionary.com/Frankenstein+Syndrome.
Normal people won't proably want them to be smart.