I'm sure that you can make it work, and make it work well. Also if the system has been factored in a given way, maintaining the factoring is typically going to work far better than degrading it.

I'm also sure that my preferences are shaped by an experience with some stored procedures which were very poorly written, which contrasted nicely with cases where the same logic had been moved into an application layer and then was organized there fairly cleanly.

And I would like to point out that when I said, "I wouldn't lean that way..." I meant that to be truly understood as a personal preference which others disagree with, and which I might choose either way on in practice. You demonstrated nicely that others do disagree, and confirmed at least one of the grounds on which they disagree. (The performance benefit from being able to rethink your database design.)

Plus finally I would like to note that the choice of which way to make this decision is not as important as who you have doing the work. Competent people can make either decision work, incompetent people (or even competent people with the wrong background or pressures) can make either fail.