I didn't mean that you need a new mouthpiece. I used myself as an example of how my body changed over time in spite of constant training. What also changes appreciably is your hearing which also is the acoustic feedback that governs all playing. After laying off for many years you have an "intelligent" new start. You kind of know what needs to happen, the mind is strong and the flesh is weak........................ A teacher can speed up developing good habits which will reap the most results fastest.