You're going to have to stop tickling it. Pick the easiest corner to get at, and give it a couple of really good hits. In fact, try the top corner then the bottom corner alternately. I don't know if a liberal spraying/soaking with WD40 beforehand would help. It is supposed to help with getting rid of adhesive stickiness. As a side note, and completely off-topic, it always makes me cringe when work is being done on my car and whoever is doing the work is really hitting something (suspension/steering parts) with a hammer. All the time, you're thinking, "My car, my car, don't be hitting it like that." And you're teeth are gritted.