Please correct me if I'm wrong, but your stating current in amperes, while your meter is displaying in mA (see video at 19:28) and your meter is connected to read mA/uA (see video at 19:47).

What I gather from this in the residential world is that the code requirements of two 10 ft rods and coldwater bonding really do not work. True?

Great video for training in relationship to Ohms Law. I use the clamp on often because it's a great time saver and accurate. Tough getting to that 25 in this Florida sand.

YOU HAVE TO CHECK OUT THE CLOSED CAPTIONS! IT IS HILARIOUS

Watched the whole video. I like the part where you were showing the change in resistance as you drive down. Once you hit your water table that is where I suspect you saw the impedance go down. I have seen where engineers focus on driving rods 20 or 30 ft to get low resistance. However, I feel it is easier and cheaper to put multiple parallel 10' rods with 10' separation. With that in mind, I wish you would have done 2 or 3 rods starting at 10'. Measure the impedance of each rod, then 2 in parallel and then 3 doing that for each 10'. I believe you would have found being satisfied with 3 rods at 10 feet deep.

Another problem with the fall of potential I have with a digital reader is that while it has an automatic frequency selector for the injection current 75% of the time my unit errors out because it can find a frequency that isn't getting interference. So I always end up using the clamp method.

Great video. In your conclusion section at the end of the video I would ask that you point out that even at the resistance levels you were able to obtain, 120 volts to ground would still not trip a 15 amp breaker. While code requires 25 ohms or less, it takes 8 ohms or less to trip a 15 amp breaker and clear the fault hazard. Code compliance is necessary, but safety is also very important, and faults need to clear the hazard by tripping the breaker.