Gabriele Oettingen at New York University has research suggesting that when we visualize positive outcomes in any areas of life doing so drains energy that would otherwise prime and support us in followup through on actions required. I would suggest to actually pay attention to your own experience, which could be that optimism medicates you into inaction, or that it does the opposite in inspiring and energizing action.
In the meantime, she proposes "mental contrasting" which is positive visualization of success blended with realistic consideration of anticipated obstacles and corrective strategies. Her research indicates this works better than just optimism, pessimism or agnosticism.
It's interesting that in the Agile Canvas process we do just that. We start with visualizing success (our stories) and then quickly move into identifying our questions: the research and decisions we need to realize our stories. It's pure mental contrasting. Now nice to know there's research supporting its efficacy.
