A standing 'paradox'

A very cogent explanation of the difference between knowing and doing. A standing 'paradox' is why great athletes seldom make the best coaches. The answer appears to be related to the difference between knowing how and why something should be done, and being able to do it without analytical thought.

Similarly, w.r.t trading and investment, not every analyst (technical or otherwise) may be a great trader or investor, and many traders and investors may be only marginal at analysis.