Every dulcimer player needs a tool box of rhythmic and harmonic performance techniques that can be deployed to make playing sound better or to carry-on in the midst of an unfamiliar tune. If you master only one such technique, learn the WID and apply it “when in doubt”.
The WID is a mainstay in the playing of one of the masters of the hammer dulcimer, Walt Michael (www.waltmichael.com). Walt often teaches the WID in classes and is credited with naming the pattern. Occasionally he has been known to refer to it as a “WAEF”. That’s pronounced “WAVE” and stands for “when all else fails”.