Cache dashboard results to improve performance when switching tab?

I'd say there are two main approaches:

1. As RobbSalzmann said, one can turn those dynamic calcs into stored formulas. You add a little more work to your calculations/consolidations, but you gain in reporting speed. This can be game-changing on some views.
2. You could export those views to reports, then display them as embedded files in the dashboard. No calculation, only visualization. If they don't need to actually interact with the numbers, this is a simple option.
3. Another, somewhat more convoluted but potentially less invasive approach, is to pump those calculated numbers into another database, and then report from there. At the end of the day, a CV is just a table... To export it you can use FdxExecuteCubeView or custom SQL, triggered by some automated job; and then you can retrieve it with regular adapters and stuff it into a BiViewer or Pivot Grid. The advantage of FdxECV is that maintenance of the layout logic remains in the CV itself.

They are both legitimate approaches, each with pros and cons. What to choose will depend on specific considerations for each Cube View.