The Apollo 13 explosion turned out to be a magnificent example of "false redundancy". By packing the three (supposedly redundant) fuel cells tightly together, N

The Apollo 13 explosion turned out to be a magnificent example of "false redundancy". By packing the three (supposedly redundant) fuel cells tightly together, NASA actually tripled the chance of losing all power. They now had three fuses that might be the wrong wattage. (As I remember what I've read, someone got but never read a memo that the fuse wattage had been changed in the fuel cell design - the memo was found speared with many others in an unread pile after the accident.) Reading the details of Musk's designs his team really does seem to understand what redundancy is and is not. It's all too easy to get wrong.