A good reason why those with serious medical conditions should not be behind the wheel.
A buddy of mine was in a serious car accident this past winter, and has since experienced a few blackouts, and as such, his license has been medically suspended. He does live in Canada, not sure if that means anything.
Still a shame that those with a history of medical conditions and the elderly are able to drive without increased restrictions or testing. If I remember the facts correctly, the elderly causes more accidents then teens (although more deaths are attributed to teens), but teen drivers have restrictions and more tests, while other age groups do not have appropriate tests.