John has the correct impression - I actually switched careers nine months ago. I now work as a programmer at a startup.

My most popular post, which brings in 20,000 to 40,000 pageviews a month, was written five months into my career (http://happierhuman.com/benefits-of-gratitude/). Everything after was less popular. Why? Because as my understanding of statistics and methodology improved, my writing possessed fewer bold and enthusiastic claims, which non-LW folk love.

I hold a medium degree of confidence in my latest posts, e.g. my one about meditation. Everything else... well I'm willing to bet $10k that gratitude, for example, can improve the well-being of a large subset of folks. But it would not surprise me if future studies showed that gratitude journals are only 50% as effective as the current batch of research claims.

If you're looking for happiness advice, positive psychology has lots of great ideas. But most interventions are less likely to help and less effective than claimed.