We used to see stripped heads at least once a month from overzealous backyard mechanics. The techs we had that did it were usually fresh ones right out of school that were trying to do as many jobs as possible in a day. It is definitely one product that a little goes a long way.
Make sure you put a little dielectric grease inside the spark plug boot and they will slip on like butter and will usually help get them off down the road. I usually put a little on a Q-Tip and coat the first 1/4" of the boot. You can do the same at the distributor cap too. You don't need to use much of that either. It's usually a 3 beer job