Ok for the double thumb technique. do you want A. thumb basically parallel to the strings strike with thumb joint, and dont use much of thumb to hit string B. slight angle (20-30 degrees) hit string with a alot of the thumb (like 25% of the end of it) C. slight angle (20-30 degrees) and just brush the string? D. Other. If so, huh? I ask because I've just started learning today off a victor video, and have been dong Option B. And now my thumb is well, really raw and hurts to play and honestly I didnt practice it that much. Thanks!