I don't see any issues with breeding 2 years in a row... if the female gets back up to size on a normal diet, and is willing to breed. If she wants to take the year off, fine by me. (i'll be disappointed sure... but I won't try to force her)
I'm not in it for the money, but I do have some projects that I would like to complete in a reasonable time frame. I think that you just have to know your animals capabilities and use good judgment.
I agree with you that BP's shouldn't be thought of as money making machines, but I don't see any issue with making money off of them if it is done in a respectful and responsible way.