I recently read an article that I thought people might enjoy. Karen Crouse of the New York Times reports that Mickelson's coach at Arizona State was looking for recommendations for getting Mickelson a caddie when he turned pro in 1992.

He looked to Mackay who was caddying for somebody else at the time. "Mackay mentioned a few candidates, and described their strengths, but he had to cut short the conversation because his player showed up. Mackay wrote Loy a note apologizing for having to hurry off, and included his phone number in case Loy had any more questions."

The hand-written note.  What happened after that? "Mickelson saw the note and appreciated Mackay's gesture. He told Loy he had identified whom he wanted to carry his bag. When Mickelson made his first professional PGA Tour start, at the 1992 United States Open, Mackay was at his side."

Mickelson has made over $75 million on the PGA Tour. Even if we estimate on the lowest end of things (7 percent of earnings with no base salary...and it's almost definitely higher than that), then that was a $5.25 million note from Mackay to Mickelson's coach.

Always send hand-written notes.

Source: http://www.cbssports.com/golf/eye-on-golf/25100797/phil-mickelson-and-his-caddies-5-million-note

Doing the right thing at the right time is the indication of a well trained "good" student. To become a "good" student requires that the student have a good heart and that the student have an earnest desire to improve.  One MUST possess both of these qualities.  If they don't then they will only go so far.  A good teacher or practitioner will recognize a well trained student.  Mickelson recognized how good Mackay was just by this one seemingly benign gesture.  That seemingly benign gesture employed at the right time is what separates the good ones from the great ones.