Steven Zeitels is one of the best vocal surgeons in the world -- he's operated on Adele, Roger Daltrey and others. Prior to becoming a physician, he did leather work, selling his creations on the street and that appears to have allowed him to develop unrivaled manual skills [0]:

Zeitels succeeded in part because of his leatherwork in college: It made him ambidextrous, a necessary skill for a procedure in which a cut a millimeter too deep would damage the vocal cords, but where one too shallow would leave some of the lesion intact, and therefore able to grow back. The problem with Zeitels’s surgery, however, was that no one else could repeat it. No one else in the field could be as precise. As he looked to publish his findings in an atlas on the larynx, one editor told him, “You can’t write that! People can’t do that!” His findings were published anyway, but the editor was right.

[0] https://www.bostonmagazine.com/2008/09/22/voicebox-hero/