I have a had similar improvement over the last year. After a 10 year lay-off (my 'I hate golf' phase). I picked up the game last year, new fitted clubs (Ping G2), and and lessons over the winter.
My handicap has gone from 32 to 18.5. I am focusing right now on no mis-hits (tops, chunks, etc.), and no blow up holes (like the 9 i posted on a par 5, followed by two birdies), and hitting fairways and greens.
In my case, I think the thing that helped me the most was really trusting my pro (we tore my swing down and completely rebuilt it), and working hard.
Now my main challenge is dialing my distances (I went from my 7 iron being my 150 club to my PW), hitting greens, and course management. Oh - and not making stupid 'hero' shots that turn on bad shot into two (or more).
So the game has completely changed for me now that I pretty much always break 100.
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