The reason that such devices are being looked at is of course, the incident that happened to Felipe Massa in 2009 and the smooth shave Schumacher had at Abu Duabi last year when another car rode up the nose of his merc and came close to decapitating him.. I agree an enclosed canopy is a no,no, but a windscreen isn't such a mad idea.
What does worry me is why this thread was raised in Military Aircrew.. cos it has nothing to do with aviation, even flight testing.. Expect thread to be closed very shortly..