Banjo Ben,
In your lesson video “Utility Rolls” under Lesson Videos - “The Utility Roll” start around the 11:40 min mark. Going from G to C to D. When you go from G to C the tab indicates 1st finger on the second string. You picked that string with your thumb when you first started the C utility roll. Is it more efficient to use your thumb or first finger or is either one correct? Thank you.