If they are simply retaining screws, then fine- they weren't fastened when they built the machine and they are now in their proper location!

It's not like I've torqued them into the rod. Like I said, I screwed them in until they touched/reached resistance then gave them a QUARTER TURN.

The grub screws are obviously put there for a reason and being fully unscrewed (as they were) clearly serves no purpose whatsoever.

The bearings still run smoothly, no crunching or grinding.

The bearings were sloppy, now they are not. Moving on...