I've never heard of 'controlled crying' -t does sound like a most unpleasant concept to me though - just from the label.
In my experience, babies cry for a reason. They are either hungry, wet, cold, hot, tired, or just a bit lonely, but the notion that they cry for the sake of it, or 'to exercise their lungs' as previous generations used to say, is frankly not on.
If your son stirs in his cot, try going in and just leaning over him so he can hear and smell you. Rub his back very gently and speak to him in a soft voice, so he knows you are there. This may be enough to settle him off.
Some children simply don't sleep through the night - our yongest was four and in Reception before she slept regularly through the night.
Don't worry about it, and don;t panic because all your friends, or maybe even youre previous babies, slept like angels, some just don't, and that's the way they are.
If you are patient, and stick to only lifting him if he really won't settle, then he will eventually sleep through - they all do.
Good luck!