The way I look at it is if the Head gasket is leaking , no matter how minor, then there are areas of the Head that will be effected by the coolant that shouldn't be , and you'll get a track through of coolant that will still weep even if you replace a broken bolt.
Picture this scenario, A guy I work with has an EF GLi, and he was towing a boat up from the Murray, and noticed coming into Truro that the car was slowing down, so he put his foot down further, little bit later the car slowed down even more, so he put his foot down further, eventually he had his foot flat to the floor and couldn't keep 80K, so he pulls over and the engine seizes as he's slowing down.
Not having a coolant level sensor on the EF GLi he had no idea that his head gasket had blown, and because of the coolant temp sensor design, his temp gauge was still showing normal, with a seized engine.
$3500 dollars later he has a recon engine in his EF, plus a Alumium boat stained with coolant.
I dont know what you think but I'd rather keep on top of a head gasket issue, rather than let something like this happen.