"No, everything I know came from what Old Dao taught me back then."
A trace of nostalgia showed in Bill's eyes.
"My maternal cousin?"
Harry asked curiously.
"Was he this... well, this good at cutting corners when he was at school?"
"Cutting corners?"
Bill burst out laughing.
"Harry, that's not cutting corners. That's understanding the rules, then using them. That was Old Dao's catchphrase."
Harry suddenly asked:
"Then why didn't he join the Advanced Potions Class if his Potions grades were so good?"
"Breaking the rules always comes at a price!"
Bill leaned back in his chair, seemingly lost in his memories.
"He was the biggest headache in our year."
"A bigger headache than Fred and George?"
Harry could hardly believe it.
"Those two brothers of yours cause chaos with their pranks."
Bill shook his head.
"But Old Dao's pranks created a new kind of order that left you not knowing whether to laugh or cry."
"Can you give me an example?"
Harry's interest was thoroughly piqued.
Bill lowered his voice, a mischievous smile on his face.
"Take Professor Snape, for instance. He was always singling Old Dao out back then, too. Of course, you couldn't really blame Professor Snape. As you know, Old Dao was hardly a well-behaved boy.
Once, he assigned an essay on changes in the viscosity of Fluxweed juice at different temperatures, requiring more than twenty observations."
"Sounds just like something he'd do."
Harry could certainly relate.
"Yes. We were all miserable at the time, because it meant staying up all night in the dungeons watching a cauldron.
But Douglas spent just one afternoon on it and handed in a perfect five-foot-long essay containing two hundred precise data points."
"Two hundred? How did he manage that?"
"He invented a spell,"
Bill's expression turned peculiar.
"A spell