I work on a couple of applications with 100% percent of the business logic in stored procedures.<p>The big downside is tooling is far worse than mainstream programing languages. Version control is doable, but depending on your workflow can be very clunky.
I think the devs have learnt this the hard way. it's not about what's technically correct or possible, It is more about getting 10 layers of permissions and signatures from higher ups before you can add or modify a stored procedure. Try doing that in a 2 week sprint and you will never touch stored procs again.