When Dan Sheehan crossed the line for Leinster’s third try, pushing the score to 17-0 just 12 minutes into the European final at the Aviva Stadium in May, fans were in a state of euphoria, witnessing what seemed like a perfect script unfolding. Here was Leinster, playing on home turf, a scenario that every player and fan had dreamed of. The team, under Leo Cullen and his coaching staff, appeared to be on a seamless path to clinch their coveted fifth star.  However, what followed was an unforeseen turn of events that would stun the home crowd into silence. What…