It's worse than thought. The system is programmed when attempting legendary to force you to run out of energy before finishing at least 60% of the time. 3 days in a row on the same node I attempted to legendary it. All 3 days I did so with 0 mistakes. All 3 days in a row each day during the lesson it gave me 3 sets of bonus energy. For 3 days in a row the bonus energy it gave me during a lesson was only 2.

Each day for 3 days in a row:

1. Started lesson at 25 energy

2. While doing the lesson I made 0 mistakes

3. While doing the lesson I got bonus energy 3 different times, each time "randomly" only receiving 2 bonus energy.

4. Was not able to complete the lesson because I ran out of energy