Static electricity is a problem in the winter in dry weather, but spontaneous reboots and frozen K3's that occur when there is no immediate contact with static would seem to be a function of the cover hooks, not static electricity. If you hold the Kindle while walking around on a carpet, then static might be a suspect, or if you walk across the room and pick the Kindle up with a bare hand, you can discharge static. But I think the static 'test', while able to mess up the Kindle, nevertheless is not the cause of most problems listed here.
My problems have always occurred after the K3 was inserted into an unlighted cover using the hooks, allowing the K3 to go into sleep mode, and after returning to the device some short time later or the next day. So far, with my one K3 (one is still wrapped under the tree for Dec. 25th), the only failures have been under those conditions and never when the Kindle has been outside of the cover.
The reason I listed keypress is because there are only two variables that could cause my problem, both of which involve the unlighted cover: pressure from the stiff cover on the keys when the cover is held down by the elastic band, and contact with the metal hooks in the cover. If static were the problem, it would affect the unit more easily when the Kindle is outside of the cover and is being handled frequently within a dry atmosphere. This is not the case for my one K3. Some situations may be different, but I am having no problem with static.