IMHO, a "fair" trade should be judged strictly on the value & stats of the players.
Everyone agrees Berkman / Crawford are comparably valued, mas o menos, each with different strengths. Or for example Berkman / Schilling would be considered fair.
Whether a trade is "fair" should NOT depend on how it will affect the standings!!
The whiny boy
who complained may be correct that your trading partner won't benefit from Berkman HRs because of a large gap between him and the guy next in the HR standings. That is not the point!
Look at it this way -- would the trade have been veteoed in May when the standings were beginning to take shape? Of course not.
I hope you're supplying your league with the URL to this thread. They should be ashamed of themselves -- THEY'RE the ones playing unfairly, not you! Good luck.