Chipper,

I have been checking the European fares for a mileage run that weekend also and the ZRH flight does seem to be the most economical way to do it. However, I will probably be leaving on Friday (just in case the Saturday flight is severely delayed or cancelled), just to make sure I get both segments in before year end. If you REALLY want miles badly, you can go DFW to CDG via LAX in both directions for about $150 more (and fly about 2,000 extra miles in each direction).
By the way, are you signed up for both the European bonus and and TTBNS? With both of those bonuses, plus Platinum double miles, plus the online booking bonus, this $491 ZRH flight could be worth about 36,000 miles (more if you are on your 2nd or 3rd European trip during the bonus period).

Mike