A great read with wider application http://spacecraft.ssl.umd.edu/akins_laws.html

Some of my favorites:

1. Engineering is done with numbers. Analysis without numbers is only an opinion.

4. Your best design efforts will inevitably wind up being useless in the final design. Learn to live with the disappointment.

6. (Mar's Law) Everything is linear if plotted log-log with a fat magic marker.

9. Not having all the information you need is never a satisfactory excuse for not starting the analysis.

16. The previous people who did a similar analysis did not have a direct pipeline to the wisdom of the ages. There is therefore no reason to believe their analysis over yours. There is especially no reason to present their analysis as yours.

17. The fact that an analysis appears in print has no relationship to the likelihood of its being correct.

19. The odds are greatly against you being immensely smarter than everyone else in the field. If your analysis says your terminal velocity is twice the speed of light, you may have invented warp drive, but the chances are a lot better that you've screwed up.

21. (Larrabee's Law) Half of everything you hear in a classroom is crap. Education is figuring out which half is which.

24. It's called a "Work Breakdown Structure" because the Work remaining will grow until you have a Breakdown, unless you enforce some Structure on it.

29. (von Tiesenhausen's Law of Program Management) To get an accurate estimate of final program requirements, multiply the initial time estimates by pi, and slide the decimal point on the cost estimates one place to the right.

32. (Atkin's Law of Demonstrations) When the hardware is working perfectly, the really important visitors don't show up.

34. (Roosevelt's Law of Task Planning) Do what you can, where you are, with what you have.

37. (Henshaw's Law) One key to success in a mission is establishing clear lines of blame.

41. Space is a completely unforgiving environment. If you screw up the engineering, somebody dies (and there's no partial credit because most of the analysis was right...)