Protective and performance grounding has been part of my profession for 40-years in telecom as a Power Protection Engineer.
Op, you have misunderstood 250.64(C) by not referring to the exceptions listed. You can splice the GEC provided they are exothermically welded or irreversible compression. The real question is why?
The simple answer; any mechanical pressure connector will fail in a short period of time buried in the dirt. Unfortunately, many do not think the GEC is important or does anything. Let's see if we can change that.
Ground serves
five functions listed in order of importance.
1. Earth Ground or GES/GEC provides the planned safe return path for lightning and utility high voltage fault currents to return to their source. We call them Sinks or Absorbers (all 8 NEC-defined ground electrodes) for outside faults in my occupation. God and Utilities are the only entities permitted to use earth (dirt) as a circuit conductor. It is the nature (physics) of high voltage. Utilities and Lightning use earth as a return conductor back to the energy source.
Utilities multi-ground the static-neutral wire on Wye distribution. The neutral is bonded to every pole butt or tower ground. The result is a very low impedance path back to the utility distribution substation transformer. The consequence is it is the source of stray voltage. If your service transformer shorts primary to secondary, or primary distribution high voltage falls on secondary distribution, earth ground is your planned safe return path back to the utility transformer. If will operate your AC service transformer fuse instantaneously clearing the fault.
Lightning does not require a direct strike to damage property or injure us. According to IEEE and NFPA, roughly 95% of transients arrive via utility, CATV, and Telco. This is why NEC 250.94 (IBT) was adopted to form a single point ground. Lightning is looking for the earth because earth is the return path to the source. Lightning behaves differently than power frequencies. Lightning flows outward on the surface in all directions, like a wave when you throw a rock in a pond. DC and power frequencies flow deep in the earth back toward the direction of the source. This makes lightning dangerous and where the term Step-Potential comes from. The distance between your feet is enough to kill.
Interesting fact and may help in understanding. Ground rods are for power frequencies, and radials (bonding jumpers) are for lightning and high frequencies. Rods are DC and Inductively couple to earth. Above 300 Hz, the impedance rises sharply. Radials are DC and capacitively couple to earth. The higher in frequency you go, the lower the impedance. Lightning discharge along the surface, and why radio towers and facilities with sensitive equipment construct their GES with very long radials going away from the protected area. You can direct where the energy discharges.
Food for thought. Think of an uninformed homeowner or ham radio operator who places an antenna mast on the opposite side of the house from the AC service. They drive a ground rod and bond the coax shield to the rod with an ADU. They do not know they placed themselves between two earth grounds. The two rods are bonded using the radio or TV as a ground wire. Classic ground loop. They learn the hard way if lightning strikes nearby.
2. Provides 0-Volt reference point or 0-volt Touch Potential as some may know it. It sounds simple enough, but there might be more to it than you first thought. Not only does it keep chassis and enclosures at 0-volt touch potential, but it also provides a 0-volt signal reference for sensitive electronic equipment. If you allow current to flow on equipment grounds, you will develop voltage potential drops along the length of the ground conductor. Result touch potential voltages are allowed to develop, and 0-volt signal reference is lost, causing errors in sensitive equipment. If all your grounds originate from a single point, no voltage differences can develop between equipment.
3. Provides the planned fault return path to operate OCPD quickly and limit touch potential fault voltages to tolerable limits. This is your EGC and bonding jumpers job. If the line conductor breaks off inside your toaster oven and falls into the enclosure, The EGC induces a high current fault, returning the current back to the utility neutral service conductor, completing the path operating the breaker within a half-cycle, clearing the fault. Additionally, the earth ground reference limits the touch potential to tolerable limits during a fault. The impedance of the Line and EGC conductors are roughly equal, forming a voltage divider limiting touch voltage to roughly half of the supply voltage. Chassis can be as high as 60-volts in a 120 VAC circuit during a fault. Note no current ever flows through earth ground, only referenced to the earth. The breaker would still operate if you lost the GES, but the full 120-volts would be on the chassis during the fault.
4. Shorts out cable capacitance resulting in a steady-state leakage current into ground conductors. Not so much of a problem in residential settings, but in large facilities are significant. The leakage flows through the cable insulation, speeding up deterioration decreasing service life. Under transient conditions, the leakage capacitance can resonate with inductance in the circuit, causing very high voltages across the loads and cable insulation.
5. ESD or pico lightning. It may not seem important, but try telling that to the dud tester at the Looney-Tunes ammunition factory. Seriously ESD is responsible for billions of dollars in property and equipment damage and countless injuries and loss of life. From grain silos to high-tech manufacturing have strict ESD controls are in place.
High tech facilities like data centers, airports, petroleum, etc go to great lengths to protect their GES. Some like the FAA and Disney parks use cathodic protection to ensure the integrity of the GES. Hopefully, no one has to learn the hard way.
OK, I will get off my soapbox now and return to the golf course.
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