When lightning hit my Dad's house, it completely vaporized the 2 position
ceramic knife switch on the tv antenna as well as the relatively small
ground wire (#10) and then proceeded to jump about seven feet through the
wall, knocking a hole about 1 foot in diameter, then jumped to the kitchen
sink and melted all of the lead out of the cast iron drain for about 60 feet
I now have a lot more respect for lightning than I did then.
If you have the antenna system properly grounded and the shield well
grounded at the tower and the tower well grounded and located at least 30
feet or more from the radio shack, then a switch should allow you to ground
the center conductor the same as a coax surge protector would do. I do that
regularly with a coax switch, but I take it completely loose when the storms
start. Just paranoid, I guess, but I can see the purple discoloration on
the radials from the antenna, where they have been red hot on many direct
hits to the antenna system.