Eliezer,

in practice do you really calculate the numbers, eg: "I calculated that hypothesis A has a probability of 73.2345% of being true whereas hypothesis B has only a probability of 54.897%, therefore I'll make an experiment to test A first."

Or do you more apply the general rules you uncovered like the conjunction fallacy and other stuff like:

Second, the hypothesis has no moving parts - the secret sauce is not a specific complex mechanism, but a blankly solid substance or force.

Peace, Roland