Something folks might want to consider is that during normal use, as in, all the time the wheels aren't being destroyed in a crash, loads on the wheels only decrease tension in any given spoke. Thus sayeth Jobst.
This didn't make much sense to me at first, but when I finally got my head around it, I realised I never quite understood bike wheels until that point. The thing about the hub standing on the bottom spokes even made sense too, believe or not.
Components of a wheel:
Hub
Spokes and nipples
Rim
Tension.