This guy has developed shallow play that he hardly may repair now, in spite all the huge work he obviously invested.
Most self-learners focus exclusively on hitting right keys and pay less attention to anything else in playing. Chuan C. Chang in his book compares piano playing with juggling a dozen spinning plates on sticks. The player have to keep an eye at all of the plates and spin up those which slowing down and getting unstable. The human attention span may not hold control of the dozen objects, but just something like four or five, therefore the juggler consciously may only periodically check in turn how few objects are doing, leaving the other objects by themselves for the time being. In piano playing, a novice might be unaware that there are other factors besides key hitting and they need close attention. There are more plates to spin then one. He/she leaves them to settle down in the subconscious mind as they are, i.e. without learning. The fact that he did not notice them does not mean that they waited and were not engaged. They were, as they are intrinsic components of piano playing, but were incorporated in the wrong and ugly way. After thousands of repetitions no doubt that they were fused into your nature and your subconscious mind stone solid. They would became your new unconditioned reflexes. To make a repair to your bad habits you should first spend about the same amount of time to eliminate the old reflexes, which took to learn them, and only then spend the same amount of time to fix new good habits. That makes triple of the time, which would be enough to learn proper habits from the very beginning. The more you burdens the issue, the more time is needed to repair.
More to read: