McDavid has been a fairly average performer in what little we've seen, and while he has yet to hit the heights of Bourque, he hasn't hit the depths of Dionne or Thornton.
Of course, if you think he's been terrible, I can't imagine how poorly you'd rate the last 2 seasons of the Crysby fellow in Pittsburgh. 3 points in 4 games against the #24 team in the NHL, followed by 2 points in 6 games vs the #4 seed in a 1 vs 4 matchup.
Can you explain why this Crysby fellow is scoring at less than a third of the rate of McMuffin over the last two playoffs?
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More seriously, I have Bourque above Crosby too. Bourque was a better player in losing in the Finals twice than Crosby ever was when winning in the Finals, though oddly enough he had his best showing in a year that ended with a loss to Detroit. At least if you want to try to rate individuals based on their individual play and aren't blindly Cup counting. In which case for McDavid to get past the 2nd round he needs to live up to Crosby's legendary 2 points in 6 games while being a team worst -3 that heroically carried his team past Washington on his way to winning the Cup via willpower.