Imo, business reasonability should be reviewed after the coder finished work, but not so much by programmer. It should be done by analyst, project manager or tester who knows a lot about the business. Basically, it should be done by person who communicated with customer or is responsible for overall vision.
Code reviews occur far too late in the development process for an uninvolved developer to provide a good, timely review of “bigger picture” concerns like business consideration (or software design) simply because the reviewing developer needs time to come up to speed on why decisions were made. In these cases it’s better to have the reviewing developer involved in a review of business requirements before the code is written. The code review can then stay focused on code.