"You could maybe pry those two difficult theories apart more, even with only one hundreth precision available, if you constructed your experiment to measure them somewhere different.
Theory 1 might say '7, 8, 9' takes 0.887s +/- 0.003s and Theory 2 might say '7, 8, 9' is 0.891s +/- 0.002s.
But then you could also do an experiment at '107, 118, 129'. Maybe Theory 1 says that's 0.567s +/- 0.003s and Theory 2 says it's 0.128s +/- 0.002s. Your hundredth second resolution can detect that difference easily, it'll make one (or both) theories lose a lot of 2s in every measurement.
You want to plan your experiments so they measure a place where your theories with the highest prior probabilities diverge more, so they're easier to distinguish from each other."