Does Cussing at your soldier immediately void your communication intent?
Course I may not know too much being an ex-savage heathen.
As a Drill Sergeant assigned to the great Fort Jackson we have been asked by our higher chain of command to not curse if at all possible. Of course from time to time your going to have those slip up's of words that just come out at the wrong time.
When I hit White Phase with my privates I sit them all down and have an AAR with them to talk about how we did as a Platoon in Red Phase and we talk about White phase. This is the first time when I really sit down with them and ask them about there opinions of the Army and the training cycle so far. I will tell you that MOST of them like it when we would cuss, or turn it up on them because that's why the joined the Army. They wanted that challenge, they wanted that Drill Sergeant in there face screaming at them, and motivating them. When you say things like "hurry up warrior, or lets go hero, a lot of times it pisses them off because they haven't earned that title yet, and some would much rather be called "numb nuts, or retard". I don't know that's just what I have gotten out of mine over the last year on the trail.
So to me especially as a Drill Sergeant, you have to chose when to turn it on and when to turn it off. Everyone is going to have there own opinion on the matter, some like it when you talk to them like that, and it works for them, and then others feel like your degrading them and talking down to them. Just have to know when to do it, and who to do it to.