Exactly what it says on the tin: a companion piece to 'Welcome to the club', containing little scenes that didn't make it into the main story for reasons of pacing, perspective, etc.
Still reeling from the revelations at Bespin – and not exactly reassured by Obi-wan's rationalizations and Yoda's last words and subsequent disappearing act – Luke had entered the coordinates for his first jump away from Dagobah more or less blindly. He had promptly come this close to splattering his X-wing all over the SSD Executor's colossal armored underbelly.