Positive Psychology versus Behavioural Economics

Both Cognitive Behavioural Therapy (CBT) and Behavioural Economics identify the cognitive distortions that humans typically make in their interpretations of reality. The idea is to correct inaccurate thinking and see the world 'as it really is'.
But one man's 'accurate thinking' is another man's cognitive distortion.
What I mean is, CBT and its younger sibling, Positive Psychology, try to teach people to take a more optimistic view of the universe. They evolved as ways of helping people recover from depression and anxiety, after all.
Behavioural Economics, on the other hand, evolving as it did out of a study of investment behaviour, typically tries to teach people to take a less optimistic, and more realistic, view of the universe.
So one of the thinking styles that Positive Psychology tries to teach is called Attribution Style. It says that optimistic people tend to attribute successes to themselves, while attributing failures to external factors. And it tries to teach young people to follow this more optimistic explanatory style - to attribute failures to external factors, while attributing successes to their own efforts.
But according to Behavioural Economics, this is actually teaching a cognitive distortion. Behavioural economists would call this 'wishful thinking' (the tendency to see things in a more positive light than they are), or 'illusion of control bias' (the tendency to over-estimate our power to influence events), or the 'egocentric bias' (the tendency to claim more credit for an event than an outside observer would judge you deserve).
The two schools of psychology agree on certain biases - both, for example, talk of the confirmatory bias, where we only use evidence from our environment that confirms our pre-existing beliefs. Both also talk of the emotional reasoning bias - thinking that something must be so, because we feel that it is so. So there are areas of overlap between the two schools.
Still, it seems to me that any of the 'accurate' ways of thinking that Positive Psychology or CBT try to teach could easily themselves become distorting biases.
Blaming others when things go wrong while taking the credit when things go right may make us more positive, it may make us feel better about ourselves, but it won't necessarily make us do a better job.
And here's the crucial question for Positive Psychology - is it trying to teach people how to think accurately about themselves or the world, or optimistically? Does it believe it's better to believe an optimistic fallacy than an accurate (but perhaps less uplifting) truth?
It seems to me that, by teaching young people to take the credit for successes while passing the buck for failures, Positive Psychology is really teaching young people how to be bad managers and dislikable people.