I would argue that they should be able to understand it to the level that they can at least defend Chi-squared as a tool for the problem at hand. Then, they sho

I would argue that they should be able to understand it to the level that they can at least defend Chi-squared as a tool for the problem at hand. Then, they should be able to evaluate whether or not it works correctly. If a medical researcher is testing a new radio-therapy treatment, but can't mathematically model every fission problem you can throw at them, they're still applying the scientific method.