Have you ever sat in a meeting where you either got the distinct impression, or were told directly that you should just use product X or Feature Y to solve a problem? Sure, we have a lot of features in SQL Server, but I don't think any of them is a complete solution by themselves.
Let's take a few examples that I've run into:
High Availability /Disaster Recovery: This is probably the biggest one. All you have to do to have a great HA/DR strategy is to have backups and install a cluster, right? Wrong! In fact, there *is* no single "right" answer to this question - it's a continuous spectrum for HA/DR, and while backups and Clustering are a part of that spectrum, they are neither the beginning nor the end. I've been to many places that haven't even done any application profiles, so that they know what data they store, how they store it, who has access and so on. You can't have an effective HA/DR strategy without an application profile.
Consolidation: Hey - companies want to save money, so of course Virtualization = Consolidation, right? Wrong! There's application collapsing, database stacking, Instance stacking and Virtualization, to name a few. Once again, you have to start with an application profile. When you consolidate, that location becomes a higher risk factor, so the application profile will help you find out what the right solution is for each one.
Resource Governing: Sure, we have a new feature in SQL Server 2008 called the "Resource Governor", and it's a great way to control access to your system and provide a good SLA. But did you know that even Replication can be used for this purpose? And you'll never guess where you start to discover the right mix - that's right, with an application profile. Hmm.... I suppose I should write an article on how to do one of those...stay tuned.
The point is, there is rarely a "silver bullet" that will single-handedly fix your issues. If there were, we wouldn't need you. You need your brain, your experiences and your judgement to come up with the proper mix of features that will solve a particular problem. There's no substitute for learning your craft and applying it well!