I agree.

2011 Programmer Cost/Benefit reality:

1) The chance my app will be so heavily used that it requires deep knowledge of many algorithms is pretty low.

2) The chance my app has serious marketing or business model problems is pretty high.

3) The extra cost of using a scalable platform (PaaS) like Appengine, Heroku or plain EC2 is less than both the cost of my time to learn or relearn all of those algorithms and the cost of setting up my own scalable platform.

I see far more business model/marketing problems than scalability/performance ones.