If I understand your question, here's an answer. I use the default camera for all positioning and then put a second camera in the scene for the rendering point of view. Whenever I have to go to the reference views, I just switch to the default camera. No keyframe changes happen on the rendering camera.... Using this technique also lets you move the rendering camera. You can even enable the 'view motion path' option and see where the camera is going, just like any element of a model.... It works for me.... Hope that helps....