Why is the Surface Pro cover magnet so strong? Calling engineers...

I have been looking at the magnetic cover attachment on the surface pro, and wondering. Is there a reason it is so strong? Don't get me wrong, it's great how quick it locks into place without effort. Way, way better than the smart cover on the iPad. I only wish they had taken the same care with the power connector, which sucks pretty bad in my view. Then I thought, is there another reason it is so strong. It gives great demo. Holding it vertically, upside down and it staying connected. Which also works on the Surface Pro (Do the test over a soft landing though !!) I wondered if another keyboard attachment that was heavier and had a stiff hinge in the keyboard, if that hinge had enough tension to hold the Pro at an angle. Would the magnets be able to survive the inclined leverage and keep the unit attached? If it were, that could explain why they are so strong. That there were plans to release a magnetic docked clamshell keyboard (most likely with a battery and more weight) That docks in the same way. But allows you to adjust the angle, via a hinge in the keyboard dock, and NOT need the kick stand. I don't have the ability to test this, but would the leverage of the unit say at 45 degrees pull the magnet apart. If it can hold it upside down, could it hold it steady at an angle? Would it need a stronger magnet in the base unit maybe, to give the support. Or would it all be a recipe for disaster, if it came "unhinged" say on a bumpy train. just a thought. If it's not that, why is it so strong?