I saw your question in the other thread, too, about the pilot - no, the schools won't know that you participated in the pilot.
I think there's a real chance that this could help for people dealing with stamina issues (most of us!). So if you were invited, yes, I'd definitely take advantage.
I also think there's a real chance (unless something goes
really wrong with the pilot) that they'll be rolling this out to everyone later this spring or summer, so the question of someone having an unfair advantage will be moot.
Here's something else to help build stamina. Don't do this all the time, but a couple of times a week:
Let's say that you're going to sit down for a 2-hour study session. In advance, figure out what you're going to do for the entire 2 hours. In fact, plan extra, just in case you finish early. Then GO for 1 hour without stopping. No checking email, no chatting with a friend, etc. Take a 10-15 minute break, then GO again for another hour, no stopping.
Then stop. Don't do the above for 4 hours straight. It's actually a lot more mentally fatiguing to study than to take a test. When studying, you're both recalling existing memories and trying to create new memories to use in future. When taking a test, you're only trying to recall existing memories.
So if you try to study for 4 hours straight, you'll be so mentally fatigued for the last couple of hours that you won't make very good memories... and your study time will be very inefficient.
If you don't do the pilot, then whenever you take practice tests, make sure to do the essay and IR sections, too, to practice that full stamina. (If you do plan to do the pilot, then you might want to try 1-2 practice tests where you just do Q and then V - skip over the other two. You can't, unfortunately, do V then Q right now. If they do launch this permanently, then all the test prep companies will adjust their tests accordingly - but that doesn't help for the pilot.)