Quoting Patrick Wiggins <paw@trilobyte.net>:
Soem food for thought (and possible discussion) from MSNBC.
Shunning the shuttle: What's wrong with the shuttle?
I liked this part: "What is this idiocy of requiring all four sensors to say the right thing before you launch? Cut the bad one out of the loop and fly with 'only' three saying the tank is full. What's the point of having redundancy if it doesn't allow you to go if one or more of the redundant layers isn't working? As you add more layers of redundancy, the probability of one of them not being able to work starts to go up. Thus if you require all layers of it to work before you take off, you'll just reach the point where the probability of being able to take off approaches zero." I agree. Speaking of redundancy, Me and some friends used to do some rather deep diving. Aside from the tanks we would normally carry, we would add a few more bottles with extra regulators just incase something went wrong and we couldn't get back to the surface without bending in half. Turns out we didn't have nothing to worry about. We used so much air dragging all that stuff around, we couldn't stay down long enough if we wanted. Of course, if we just carried MORE air... What does this have to do with the space program? It merely illustrates the absurdity of too much redundancy. Or, maybe not.