when chording, there are many uses for thumb over the top. Many great players have done this, but when playing single notes and needing to move fast on the neck, thumb on the back is preferred method. And it is something easily corrected.
Bad habits are not dead ends, you can learn correctly, it just takes will power as at first you will say to yourself that I do it easily this way why change, but once changed and seeing the benefit it becomes evident why. You just need to get over the effort it will take to relearn.
Kinda like a ball player,you get a guy who does it one way and has success in little league, now his 2 buddies who are not as good go off to baseball camps and play school ball where they get professional training instead of the local sport nut father of so in so being coach in little league. They learn to correct this and that and the next thing you know they are playing in college or in the minor league. While the guy who was good in Little league, but got no formal training went on being able to do it at a certain level, maybe better than a lot, but never made the JUMP that can be made with training of proper technique.
Same thing happens with music, there are 2 things you learn that make you so much better than others if you just practice, first is proper technique so it is easy, second is theory so you fully understand what you are doing.
Walk into a Jazz Jam session, they will say ok we are going to play this song in the key of such an such, they pass out a chord chart, that chart does not have chord names on it, it has chord numbers like llm7, lVdim, and it says Nat.min, then the drummer strikes a beat and they all take off. all the info they need is on the chart, the rest is from Knowing Music and theory.
It is just a mater of where you want to be. Not everyone wants to be Fluent. Most are comfortable being able to play the music they heard in High School the rest of their lives,playing around campfires and stuff. the next group go out and end up in bands till they are 24 or 25, then there are the guys who go out and Jam till they are 50, My gorup is those who play in bands all their lives, just messing around and having a blast. then there are the professional musician.
And besides that are rock stars, most of who will have a career 3 albums and then fade out to the where are they now file, they make some good money but end up squandering it all thinking it will be coming in forever. Rock Stardom is pure luck and many are rather poor musicians, but stardom does not require a lot of talent, just good luck. Just look at Tom Delonge.
