I have to agree with Ben on this one - Authentic Swing it is. I can literally name guys in my club by there swing, i could do this 3 years ago - i can do this 5 years from now, doesnt matter how many balls they beat or how many lessons they take. That doesnt mean they dont improve their ball striking, but their original look of the swing will stay the same. Looking at my swing 1 year ago and now, i´m shocked how similar it looks, yet i hit the ball much better. Looking at impact, i indeed see an improvement, but thats something you wont be able to catch with the naked eye, only as a result in ball flight.
What you will frequently see are backswings and finishes, and as i read a comment of Johnny Miller yesterday - doesnt matter what you do you on your backswing, you have the strangest backswings make it work, what matters is after the backswing and thats what most people cant see.
Tiger went through some coaches over time, yet to the naked eye (and without slowmotion cameras) his swing appears rather similiar in certain positions - its just what he learned as a kid and grew up with, and changing it to a big degree is not possible.