Aurora810, I agree with you.
No matter how "normal" you want to raise a future King, the bottom line is that he will be King.
On the other hand, it is much easier to have Christian have a normal lifestyle now that he is one, rather than in his teenage years and twenties when he'll have to understand his place in society.
To be a good royal, you can't be that different from the people, so when Christian is CP or King he'll be able to remember and utilize his "normal" experiences as a kid growing up.
Also, from what I've read, Frederick had a very "royal" childhood, didn't even seat to dinner with his parents till he was much older and was always with nannies. I think he regrets that and doesn't want it for Christian.