Feature Request: Ability to add measurements at run time

It would be nice to have the ability to add measurements during a test. For example I am testing two products that are identical with the exception that one is single phase and the other is three phase mains. One test requires measuring phase volts. During the test I know if I am testing a single or three phase unit. I would like to be able to add the additional two phase measurements only when testing a three phase unit. Currently they are all added via decorators and I have to just set the unused measurements to passed for a single phase unit.

Thanks
Ashley