How much grounding do you need?

More grounding is usually better ... BUT ... be sure your grounding radiates from a single point and doesn't loop back. When you have created a ground connection be sure any additional grounding does not parallel that path. If something is grounded by the rack frame don't run another ground from that equipment back to the grounding point. Make sure your signal grounds are only tied to a single point (don't ground both ends of a signal shield)

I used to work with an MT BELL engineer. He said that more diameter is not as good as more surface area when it comes to high frequencies. Think about using these

making your own with welding cable. He showed me time and time again that a 4 inch by 1/4 plate around a room did better than all the ground cables we had been installing. We even installed a bunch of 8 inch wide copper foil in one server room. I do assume that this is for equal potential and not for the circuit. Right.

I always run a ground wire, metal conduit and then braided straps. Have not had any problems yet. More is better the faster you go or the smaller your trying to measure. IMO

Agreed, multiple ground paths are best. Certain length conductors act as open circuits for very high frequency signals. In this respect, the chassis ground is the better ground, as long as the joints in the chassis are electrically conductive.