had one required here when the house was built, but it hit a rock and about a foot of it is sticking out and it's right beneath the meter on the north side of the house.   well uses plastic pipe into the house, so i had a second rod put in back of the house and connected to the hot water pipe which pretty well connects to all the plumbing in the house.  it also sticks out about a foot, but no complaints on inspection (don't think 2nd one was even required back then).   

 I have to agree with @Artie the NEC is a minimum requirement, locals can always ask for more.

When I was an apprentice working with a journeyman in a electrical room we had to turn the power off to a breaker that also fed the light in the room, the dead front was off the panel. He turned off the breaker before I turned on the flashlight and when I did he told me to turn the light off. He then showed me a little blue arc coming from a breaker, with the light back on he showed me that the screw on the breaker was never tighten and the wire had welded itself in place and the arc was from other strands of wire trying to make connection. Don't know how long it was like that but from that point on every time I was tasked with terminating a panel before I put the dead front on I would double check every breaker.

 In commercial panels there are 42 breakers plus neutral wires & grounds, its easy to miss a wire from a little distraction. Over time I have missed some and found some others have missed before me and was glad for the double take.

The reason for not installing the bonding screw in more than one panel is you are grounding the neutral again.   Once you do this inside your home you have a parallel path for neutral current across the ground wire.   Regrounding the ground wire is fine such as different panels but not regrounding the neutral.  Roly

Many years ago an old electrician demonstrated a neat way to install a ground rod--- in non rocky soil----start by installing the rod about a foot -than withdraw the rod- pour in some water-and by hand start pumping the rod up and down-and the rod will easily go down-many times to the full depth. Really it works and am still of good mental capability.