One of the opinions that was expressed yesterday by our developer friends (a bunch of Regional Directors – and look, Kimberly's the featured RD today on http://theregion.com/) is that SQL Server is just plumbing. Consider the developers (or app architects) as plumbers. They see SQL Server as a few pieces of copper pipe joining a few parts of the app together, with maybe some flow control in there somewhere, like below. (You might need to right-click and select 'show picture' – I don't know why – I just do databases :-))
There shouldn't be anything in a piece of simple copper pipe that impedes the water flow, right? That's what you'd think. The problem is that mental model of a simplistic data store is wildly inaccurate. What they think of as a bunch of simple copper pipe and some taps is a really a very complicated machine, like below.
There should really be another step in the software development lifecycle – during the design phase, there should be a question that says 'are you doing anything with SQL Server? (Y/N)'. If the answer is 'no', the lifecycle model continues. If the answer is 'yes', then STOP and consult a DBA or database-savvy developer. Just like working on a house, most people will call a plumber rather than mess around with pipe-work themselves.
Kimberly's going to pick this topic up big-time on her blog – keep watching there!