The Toughness granted by Minos Legens, as currently implemented, allows access to the Toughness enhancements. These enhancements remain even if the helm is later removed. As I see it, this is a somewhat gray area, and there are two parts that could use some clarification about whether or not they're bugs:
- Should the Toughness granted by the helmet open up enhancement lines?
- If the answer to #1 is Yes, should the enhancement lines remain if the helmet is removed?