Factorial Designer: wrong error message when num. of values doesn't match 2^k

[internaut]

"factorial designer won't let you set k = 2 -- it continues to throw an error about k = 3, even when you provide the correct number of outcome means."

-> it works, but the problem is actually the wrong error message

See this tweet: https://twitter.com/notanastronomer/status/1219724163910234113