737NG Panel Configuration

Good day all.Just a question regarding the real life operations of the 737NG.When in the PMDG aircraft and using the engine instruments to show on the lower EICAS for secondry engine readouts the panel can also be used to show control surface commands/movements.However, when you set the engine instruments to be all on the upper EICAS, the lower EICAS is inop. You can't get any reading of the control surfaces. Is it like this in real life? I have looked on Airliners.net for images and it would appear so.This is not bothering me, I was just curious as to why this would be made this way by Boeing. What is the point of installing a lower EICAS for customers who go for the second option?I hope this makes sense.Many thanksDale.