Hm... I can't say for sure, but I always assumed pulling a stunt like that would play merry hell with the sleep cycles. People with sleep apnea often have problems associated with lack of sleep due to waking up during the night. It doesn't matter that they are only awake for moments, or that they get the recommended hours, because the sleep cycle is constantly interrupted. I'm assuming "micro-sleeps" would have a simmilar effect.