Connection between the two of them

Seeing Killian's widened eyes, she let out a chuckle. Caressing his jaw, she said, "Surprising, isn't it? How could a boy who could solve chemistry olympiad questions at eleven and solve mathematics problems just in mind, can fail high school?"

Killian had no way to answer her question. He was shocked and confused beyond words. He didn't know what to say. Could it be that what Emma was trying to tell him was correct? No, he didn't think she would lie to him. But still...how could his research be wrong? 

"No one could disguise better than him," Emma further told him. "He makes you think about what he wants you to."

"Then why did you run away from the marriage if he was so amazing as you make him sound?" Killian asked him. If Salvatore Marino was so great as Emma was telling him, then why did she leave him at the altar?