I'm not sure I understand the question. However, the double agent is a defensive specialist. Whenever an enemy has a large force coming at you, you send out the DA and it kills all the drillers and swaps ownership of any specialists involved. You lose the DA in the process but he can be regained if you engage in combat with him again or if you hypnotize him after taking you opponents base (probably a hard task since you opponent now has a DA) otherwise your opponent will just take the DA and use it however he wants, but you bases will be successfully protected.
My faith has found a resting place,
Not in device or creed;
I trust the ever-living One,
His wounds for me shall plead.
I need no other argument,
I need no other plea,
It is enough that Jesus died,
And that He died for me.