[conistonwater]

Obvious or not is a bit of a red herring. The key test should be whether somebody would have done the same thing without a patent. If they would have, then a patent is unnecessary - the government shouldn't be in the business of granting arbitrary monopolies, only those monopolies that specifically promote something, for example, research. If a patent is granted for a thing that would have been done anyway, then that patent is a kind of a dead loss for society.

In the case of flux I think it's relatively clear that it would have been done without a patent, but maybe some people would disagree.