OK, I'll chime in, although it will most likely be lengthy...
Let's establish a few electrical facts first;
If a piece of equipment comes with a two-prong (hot and neutral) plug then the chases is bonded and passes any short to the neutral.
If it comes with with a three prong (hot, neutral and ground) then it most likely has an isolated chassis, meaning if there is a short to chasis the ground takes the load. If it has been replaced with a two prong cord then it is just waiting for anything to give the short a ground (meaning YOU!).
Let's try to clear up another misunderstanding; the wrapping of a foil shield or 'drain' around a wired connection between two pieces of equipment is not for grounding but to stop RF ingress. Back in the 'day' when I was doing instrumentation this was only terminated on one end to drain off any interference it had stopped and NOT bonded between two pieces of equipment.
Now for the jobs of ground and neutral. A neutral is to provide a return path for a 120 or 208 VAC circuit. A ground is to provide over-current protection. End of story...so far.
In a typical U.S. residential distribution panel you have two opposite phase 120 VAC circuits and one neutral coming from the utility. In the panel every other circuit is on the opposite phase and each circuit has its own neutral (actually if two circuits in a particular run are opposite phase they can share a neutral but nevermind...) and each circuit has a ground. The neutral return to the panel to the neutral bus and the grounds go to a ground bus that has a number 6 wire going directly outside to a groundrod and then they are.......BONDED! So.....what gives??
If you were to go and look at the utility poles the come to you house (provided they are up to IESC codes) you will notice a ground wire coming down each pole to the ground and that each utility on that pole (phone, cable, fiber) each have a 'bond' to that wire that originates from the neutral wire which is typically the bottom wire in town and the top wire in rural areas. This is the ground plane. The ground rod at your home adds to this as a stop-gap from surges TO YOUR HOME. It is NOT where most of the ground and neutral goes from your home. Why? Because a circuit looks for the shortest route to a ground, and that "ground" mean the least amount of resistance. Your paltry groun-rod most likely has a high resistance value so the bond between ground and neutral is to use the utility's ground plane (over the neutral) to absorb over-volatages cause by shorts and shorts to ground. In other words, if a short were to rely solely on your ground-rod with a high resistance, it would be like a long line at the grocery store, and the utility ground is when 10 other checkers open up their lanes then all the customers run to the shortest line.
So now that we've established what the ground and neutral are for, what causes a ground loop? In my experience of dealing with humbars on TV channels it was because there wasn't ENOUGH ground between the pieces of equipment so the answer was to always make sure everything was bonded together. In most cases this alleviated the issue.
