I always took that quote to mean that, although we may learn massive amounts of information on a subject, we don't always back that knowledge up with the prerequisite knowledge needed to to fully understand and apply the information. I think this is simply a side effect of a mind with frequently changing interests. For someone who has had the same special interest for an extended length of time, they may acquire that background knowledge. But for someone like me who changes special interests more frequently, it would be nearly impossible to acquire applicable knowledge in every special interest I take up.
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Damn good, bloody good, damn good job.