Working in some average time taken for these methods may be useful as well. That's going to be somewhat of an apples to oranges comparison, but I'd wager the time savings between some may not be what we'd expect.
It would be pretty difficult to find brewers set up to do all 3 in an optimal fashion. And what would you be looking for? We need a hypothesis, guys!
It's not really an experiment, more just data points that may prove interesting. Let your experimenters brew on whatever setup they have, and just have them record the amount of time required for setup, mashing and lautering, and cleanup.
Setup would be everything from adding/heating water through to doughing in.
Mashing/lautering would be the time from doughing till all wort has been collected in the brew kettle.
Cleanup is self explanatory.
I think a standard mash schedule would be important, but that would already be the case if your testers are using a standardized recipe. Then just run the mean/median/mode numbers for each activity for each mash method.