You're right that "sure" is too strong a word- I should have said "I have a hunch". The hunch is because stories like this https://www.quora.com/What-is-known-

You're right that "sure" is too strong a word- I should have said "I have a hunch". The hunch is because stories like this https://www.quora.com/What-is-known-about-Elon-Musks-long-time-assistant-Mary-Beth-Brown https://www.quora.com/What-is-known-about-Elon-Musks-long-ti... about Elon Musk are not uncommon.