I think it's because some topics are worn out from what I've seen pouring through the forums. This has definitely been hashed and re-hashed.
This experiment in particular (In my opinion) is the most ridiculous of all of them, since it can be easily reproduced by anyone in favour of a spherical, or at least curved Earth.
Regardless of how many Zetetic or otherwise publications one might find stating data pointing to a planar Earth, the fact is, as Tom has so often pointed out... not all sources are reliable, and if you aren't / weren't there to witness it for yourself, you really can't be 100% sure.
The argument can swing both ways no matter how much anyone wants it to be set.
The fact remains that if you take the experiment out of the context of the books, take it into a standard, open world environment such as the salt flats, or a large body of water like the great lakes or a calm ocean... use the best telescope money can by that best fits this experiment... it's going to reveal the fact that there is a curvature to the Earth.
The way to prove there is not an illusionary artifact is to to a ground experiment such as on the salt flats with a vehicle, and a small flag mounted to it. Have it drive off into the distance until it slowly vanishes from your telescope (that is mounted to your vehicle - truck bed, trailer, whatever) then as it dissapears from bottom to top of flag, radio for them to stop. Then simply start off slowly toward them, keeping them in view so as to eliminate the possibility of there having been an optical illusion.
Since you are keeping them in view, you will notice any 'flipping' 'wavering' or instant jumping of the image as you approach the original vehicle.
Unfortunately for FE theory, you will simply watch as the flag, then the rest of the vehicle slowly reappear.
Like I said, that's my opinion.
Optimus