Dashboard - Multiple Dynamic Date Selections to create Base & Comp Period Calcs

[adam_mc]

For CA 11.1.1:

In a Dashboard based over a Data Set with various measures aggregated by date, I need to create multiple dynamic "prompts/filters" such that I can create Base Period & Comparison Period calculations and present them on the same widget.
I know how to create two Date "prompts/filters" and break their attachment and then display the results on two distinct widgets, but I am struggling on how to combine the results on a single widget.

Is this possible?
If it is not possible, has anyone encountered a similar request and how did you present a best possible solution to the business user?

Any suggestions would be greatly appreciated.
Thanks in advance,
Adam.