That reminds me of all the bad tests of numerical algorithms you can write if you use numbers like 0, 1, 2 as test inputs because:

- 0 * x = 0 so you don't necessarily test the correct computation of x,

- 1 * x = x so you don't necessarily test if you actually use the input 1,

- 2 * 2 = 2^2 = 2 + 2 so you can get some pretty weird masking.