"I do run around with just the front case in as well, but not too often as I don't want to blow the input on the rear case."
I am considering duals and also have some questions. I currently have a 4.70tcase and 4.88's locked front and rear. I have to say I miss the 2.28 in the snow. I do as others have stated and shift the tranny to get the rpms I want but have often wondered that if I had duals, I could just run the front 2.28 and be good. According to the above post this may not be such a good idea. Or "Big thing is don't run the front case in low and the rear in high and get bound up, things will break."
So my question is, what should you NOT do with duals?