A really good ground however is highly desirable, as tying everything, cable service, phone etc, to a really good house ground goes a long way to preventing hums and buzzes, and can't be a bad thing in helping to prevent lightening penetration.
Tying all the systems to one common reference ground is indeed a very good thing. Early on in the "day", it became understood that untoward events could easily cause a difference in potential between lines coming into a building if they earthed at different locations. The events are in several classes..
1. Faults in the power delivery system that passed the unbalanced neutral currents through the earth. A three phase high voltage system where one phase load drops causes neutral currents to flow, and this can actually cause voltage gradients
across the soil of the properties. Indeed, the residential delivery of power on the east coast has every second or third pole earthing the neutral, and this results in 5% to 10% of the neutral current returning to the pole
via the soil (not to be confused with the term "earth"..) On the west coast, they use what is called "two bushing transformers", which isolate hv neutrals from residential neutrals. On the east coast, the pole transformers are actually auto-transformers, and the residential neutral is shared by the hv distributed grid neutral.
2. A nearby ground to cloud strike. This produces voltage gradients, generally in a circular pattern around the point of hit. The gradient generally falls off as 1/R or 1/R squared depending on ground conductivity patterns, but there are some geologic conditions which squeeze the current linearly..like moist soil layered over non conductive rock.
3. A nearby ground to cloud, or cloud to cloud, which causes reference differences based on loop induction. Generally falls off as 1/R, and is dependent on the loop angle of incidence..note that this effect is the very reason whole house spd's cannot protect two port devices...the loop formed by the signal wire ground to power delivery ground can generate transient levels which the appliance is not designed to survive. This is where two port spd's are the ONLY way to stop induced voltage transients. (
edit: This is a very important issue for the power companies, as the distribution grid is very large, so lightning caused induction based transients must be dealt with at the grid level. This is also very important for high energy physics accelerators which are hundreds to thousands of meters in diameter. Dielectric breaks around the ring are necessary as are prevention of loops formed by common supplies feeding magnets around the rings.)
W-dude always mis-apply's Martzloff's "upside down house paper" with the chicken little shtick of "spd's don't work"...what Martzloff
actually does is outline how reference potential differences as a result of incoming lines on opposite sides of the house can destroy appliances which are two port.
The Mike Holt website has quite a few articles from
real professionals which detail the typical power delivery problems, it's a good place to peruse.
Cheers, John