Well, do you make shihonage in four directions? And do you make tenchinage all the way from heaven to earth?
Kokyu means breathing out and in, and I guess everybody is doing that...
About breath power, kokyu ryoku, I don't think you can think of it as an on/off switch. It will increase by time, through training.
And it is not necessarily so that kokyunage should be done as an expression of kokyu ryoku. To me, it is mainly an exercise in blending with the partner, and leading the attack on.
Breathing in corresponds to accepting the attack (joining with it), and breathing out is leading it on.
If I hasten to use kokyu ryoku power to throw the attacker away, I am not sure that I am doing aikido.