In his book Pro's Pros, "Extraordinary Club Professionals Making Golf Great", Joel Zuckerman has written several pages on 30 different PGA Club Professionals.  I have locked onto one particular Golf Professional.  John Dahl, Head Professional at Oxbow Country Club in Fargo, ND.  To summarize the key points I have taken from the comments regarding Mr. Dahl:

• Fully half of the 300 Members of his Fargo Club maintain single-digit handicaps.
• Dahl estimates his younger students have earned in excess of a million dollars in college scholarships.
• He usually only teaches three lessons a day, but he does plenty of five or ten minute fixes also, in the shop, in the grill room, wherever he is asked.
• He promises that new Member, the 25-handicapper, it they are willing to jump in the cage with him and work on the game in the manner prescribed, he will drop to an 18 that first year, then down to a 12 the next season, and then single digits after that.  "I make the promise because I've never been wrong..."

Want to drop your handicap?  You should start with the putting green.  Learn to two vs. three putt and you drop strokes immediately.  Learn to chip up and one putt and even more strokes will drop off your handicap.