I tend to agree with you; unless I have been told it is my duty for the class to correct a partner, it does interupt my training to do so. I'm in kind of a wierd place right now regarding responsibility most of the time, so its not as simple as it used to be. But I think for most students, if you are training, you are not teaching. I know the 7th dan where I got my first kyu used to be pretty strict about that.
Actually, if both shite and uke pay close attention during practise, it is possible to pick up a lot from each other without talking at all. I try to focus on my partner in such a way as to lead a jr student through the technique as I understand it, and to follow a sr. student through the technique in the same way. No words are really necessary if I use the correct focus and intent.
Of course, different strokes for different folks, and different instructors might prefer a different method. I certainly wouldn't blame ego for your method.