A lot of tests, especially on things like how a community reacts to a certain set of circumstances, would be rendered useless if the participants knew that what they were doing was a test.
A good example of this is the Milgram experiment where they told participants they were taking part in a study of memory and learning but it was actually on obedience with authority:
en.wikipedia.org
Ah yes, for stuff like that it would!
But for SC, it wouldn't make much of a difference I think.
There is avocado for a reason! AFAIK they do get told what to concetrate on, what to try out and test before it goes into wider ptu. Then there were times when even the open PTU got told they should be doing X at Y time on a day, to do mass testing. This is enough to set up a baseline for balance/ see if stuff is working at least kinda like it's intended.
Then there is the live enviroment.
In the PU, it all evens out and returns to a neutral state where everyone does what they want to invest their time in, regardless of the fact that they are told or not told what to test.
If bounties are the only time efficient way of earning UEC, some of us might do just that. If it's mining, then that, especially since the ROC is so cheap and easy to get.
There are loads of ppl who just want to muck about with their friends doing stuff that's irrelevant to any sort of focused testing CiG might want to see.
There are those that just want to explore, see what sights they can find around the moons and planets.
Then there are those who just wanted to chill and do something while watching stuff on another screen and want to do box runs or trade, low effort low risk stuff...
I think this testing can only get us so far in balancing the game, and everything will need to be totally re-balanced once we get a proper working economy with fully fleshed out dynamic supply and demand, insurance w dynamic claim times, and ofc missions, all between multiple star systems. Whether we in the PU are told what's being TESTED or not is irrelevant to the outcome at this point.