[jrref]

This is what many don't understand. From a high-level, when you have a storm and ice crystals, etc, are moving around in the clouds over your home, they are developing a strong negative charge. Conversly, you home, trees, and you if you are outside develop a positive charge. When the charge between the cloud system over you home and any of the things I mentioned is strong enough, there will be a connection, i.e. lightning strike. This is why homes are struck eventhough there were tall trees, a tower, etc,. near by. All lighting rods do is create the best charge so if there is a connection it will hit the rod and be transferred safely to ground vs hitting anywhere else on your home or you if you are outside. And yes when a connection is made the current is incredibly high but the duration is extreemly short which enables the Air Terminal (lightning rod) and it's connecting cables and ground rods to pass the charge safely to ground. If you understand these details of the strike you can see you won't get an incredibly large bolt that will over-power the lightning protection system. Lightning is not some large power source randomly striking the ground like a star wars laser system. There needs to be a recepter for the attraction and connection to occur. Also want to mention, in some cases a lightning rod can "bleed-off" charges over your home to prevent the connection or strike. I've personally seen this occur.

As far as that person's irrigation system getting burned out via a strike down the street, correct, a lightning protection system on your roof would have not prevented that. You need a good whole house surge protection system to protect the devices in your home from these events. And don't forget if you have cable, you need a surge protector on the feed coming into your home as well since a high percentage of induced surges come in from that feed. If you have fiber you don't need to worry about that.

At the end of the day, although getting hit by lightning is a very low probability, if and when it does happen it will be a life changing event for you and your close neighbor and you will be regreting not spending the $3,000 ish one time cost to protect your home and your family give we live in the lightning capital of the USA.