Jose wrote:
Boy, I hate to be pedantic about this, but in a vacuum the heavier
object _will_ reach the surface of the earth faster than a lighter
one if both are released the same height above the ground.

That depends where they come from. If you pick up the feather
(leaving the stone on the ground), the stone's mass is part of the
Earth's mass.
If you then drop the feather and pick up the stone, the feather
becomes part of the Earth's mass for that experiment.

The total mass is the same.

But suppose the "stone" is half the earth!