But isn't this because 9.8m is nearly 2 percent of the radius of the Halo you used? The larger the Halo, the smaller percentage difference in the velocity at any height above the ground. And obviously an Earth Halo is dramatically larger than 1 km across.
Yea... I agree... and I added an edit to show that. On this point we're mainly disargeeing on a matter of scale. Even at earth sized halos 1 cm in 9.8m should be easily detectable. We may have to go larger. A lot larger.
I may try one more thing... specifically, instead of merely dropping the ball, what happens if I throw it perpendicular to the pole? This also happens to be in the chord direction which is essentially the direction of travel. So... this should really screw with the fall rate. On FE/RE these two components of motion are orthogonal to each other ... here, they're parallel. (as a matter of fact, this observation cinches it.)
Note, I kinda want these to be different so that "we" can point this problem out to Bungie and they'll issue this correction in Halo 4.