That is a chilling statistic.
As a VFR pilot, I often wonder what would happen inside a cloud to make me react and rip my plane apart in under 3 minutes.
Dramatized:
I'm sure a pilot in dense cloud has the potential to make a whole host of mistakes. First I'm sure without instrumentation a pilot would quickly lose gauge on how level they're flying, or second guess how level they're flying and try to adjust. If you get caught in a cloud with a very low ceiling, there's probably not much time between exiting the cloud and that "Oh shit, that stuffs the ground". Or a slight climb and not enough thrust could easily compromise your speed and put you into a stall.
I'm quite sure 3-dimensions of travel is a real bitch when you're blind and can't stop.
As a VFR pilot, you've received basic instrument training. Remember that training, trust your instruments, and you'll make it though.
Untrained, never having touched the cockpit of a plane, I can get the meaning from these instruments. Is it simply that pilots fly without these, or that they simply disregard them during flight?
As the original article pointed out, the first reason is that the sensations are so compelling that doing what the instruments tell you will feel VERY unnatural and you will keep thinking that your instruments are broken or stuck (hence you HAVE to trust your instruments). And even if you remember not to trust your instincts, you will still often unconsciously apply slight pressure to the controls.
The second reason is that for every change in the plane's orientation and speed, several instruments will start moving at once. Without training it is very hard to integrate what the 6 instruments are telling you into a complete mental picture of what's going on with your airplane.
People driving cars in simulators also do worse than in the real thing - a simulated car doesn't have all the ways a car tells you that you're driving close to the envelope.
One of the reasons it's done this way is to teach you to ignore inter ear cues and trust your instruments. Your inter ear senses acceleration, not absolute motion. Couple that with the centrifugal force during a turn changing your perception of which way "down" is, and your body responses become one of the main reasons you get into trouble.
It's similar to banked turns on car racetracks. When you're in a banked turn, "Down" for you is no longer towards the center of the earth, it's at an angle, perpendicular to the speedway. You also loose the sensation of turning once you're in that banked turn long enough (specifically once the fluid in your ear settles down and stops moving). If you were driving with a blindfold, you wouldn't be able to feel how steep your turn was.
[1]: http://sportys.com/pilotshop/category/864 "View Limiting Devices"
I guess what I was getting at was not so much that you could survive with your inner ear, but that you get a lot of feedback from a vehicle that you don't in a simulator. That's not relevant to this study if they didn't use a simulator, though...