Two points.
1. I think its obviously too late for trading this season, but these discussions are useful regarding future seasons.
2. What about having two roms after the trading period: pre-midseason-trade and post-midseason-trade. The first rom is used for the first half of the season, and even AFTER the trading period, it would be used to play any back games from the first half of the season. This way, everyone would still be required to play an equal number of games with their pre-trade and post-trade teams. Also, we wouldn't have to wait for everyone to catch up prior to the trading period. It's still a little time-travely, but a better option than having a huge break in the middle of the season.
D, is it possible to organize the database to handle this? the roms would be named differently so you could have the system recognize whether the rom was pre-trade or post-trade, and it could allocate the stats accordingly.