Frankly, I'm not a fan of those "no pressure" comments either.
It's representative of the sort of lackadaisical approach the team took to the regular season. While the playoffs aren't completely analogous to the regular season, I think everybody would agree that you play how you practice and at this point in the season a team basically is what it is. The "switch-flipping" argument is mostly a a myth. So if the Celtics think they can walk into this series with "no pressure" and then pull out a win, I think they're sadly mistaken.
Sure, the talent is still there. But what's going to motivate them to go extra hard for the rebounds, charges, and other hustle plays that make or break a championship team if there isn't any "pressure"?
This team lacks the intensity of the 2008 team, so naturally I'm going to dislike any comments that remind me of that plain fact.