[necovek]

Sure, a lot of the scientific findings are frequently established before they are formally verified/repeated (and even in "proper" science, it's common to have a hypothesis that you set out to prove) and people can practice them without having any scientific background too.

That is exactly what I think makes something a scientific success: ability to apply the findings without understanding the nitty-gritty.

Sales is definitely a success of applying psychological results too: consumerism is the definition of the current age (in Western hemisphere, at least) mostly because we are driven to consume to the extent we are.

Of course, it's important to remember that psychology, just like most social sciences, is statistics-based, thus none of the results apply on small numbers and especially not on an individual.