No, the opposite. IF you roll 16-20 you have to roll again and take the lower of the two dice. If you roll 15 or less you don't.Also how would disadvantage work? Using the climbing example with disadvantage 16. So I roll a 15 on the first die and with my Athletics it should be a success. But because I didn't roll a 16 I have to roll again and succeed again or its a failure? I feel as though that would be worse than how disadvantage works now, mood-wise. I could be wrong.