Is that necessary? You don't have to extend it all the way.
I personally think having a second "ball" to the inside of mine is going to be weird, I'll have to see. It rained today so no practice.
Yea I'm not a big fan of the golf balls at all. They could have just used flat discs or something so the whole thing sits nicely on the ground.
I stuck my speed square on it and it passed the eye test.
Alignment sticks are good but they don't line up perpendicular to each other well and they are very easy to knock out of alignment if you aren't careful. They are good tools certainly but I think the HackersRx does what it does a little better than alignment sticks do.
I do like the measurements in theory. I don't know how easy they are to read in practice. I might end up using some colored sharpie to mark out important spots to me.
The ball on the end of the center rod makes it really easy to practice your ball position at home. Just put a club in your hands and set up at address as if that was your golf ball.