As an analyst, I was first exposed to baseball and only got into basketball later. I've always tried to make an effort to recognize the areas where approaches in one sport do not apply to the other. One of these is the treatment of the playoffs.
In baseball you can safely ignore the playoffs when discussing where players rank on the greatest of all time lists. There are fewer teams in the playoffs, fewer rounds and games, and the regular season is twice as long. I estimate that an average baseball player will play about 1% of his games in the playoffs. The maximum in a season is (as of 2012) is 20, or 12% of the regular season.
In basketball, an average player plays about 7 percent of his games in the playoffs, and a player who maxes out the postseason (going to the finals and playing to 7 games in each series) will play 34% as many postseason games as regular season games. It's even more extreme this year with the abbreviated schedule.
In baseball the argument for mostly ignoring postseason stats in player evaluation comes down to small sample size. There aren't enough games for the stats to be meaningful (look at Billy Hatcher some time) and usually it's such a small amount of games that it's not going to change an evaluation anyway, with Mariano Rivera being a notable exception.
In basketball I think a better argument could be made for looking only at postseason stats than for looking only at regular season stats. In the regular season you have three types of teams:
First tier teams are your championship contenders. These teams know they are going to the playoffs, the only question is which seed they get. Younger teams of this tier might play at max effort and put up 60+ win seasons. As they get older and have taken a few trips to the playoffs, the regular season means less to them, they will approach it more as a tune-up for the real season. Towards the end of Shaq's Laker run, he would use the start of the regular season to have necessary surgery, miss the beginning of the season to rehab, use the rest of the season to get into shape, and come out at full force for the playoffs. You didn't think he was going to do surgery and rehab in the summer, did you? That's his personal time.
Second tier teams actually have something to play for. Some of them are going to make the playoffs as lower seeds, some will stay home. They are unlikely to go far if they get in though, they are mostly fighting to see who gets to be knocked off by the top contenders in the first round.
Third tier teams are the hopeless dregs of the NBA. They can play for pride, they can play because they don't want to keep getting embarrassed, or they can play for pingpong balls.
In contrast, the playoffs are the time when you can be sure everyone is giving max effort and trying their best to win. There have been many years when I barely bother to watch the regular season, and tune in when the playoffs, the real season, starts.
Next post I'll present the 12 players who turned their games up the most in the playoffs.