OK, so all the comments made so far have been helpful, IMO.
To answer MattNY re: why placing an absentee bid has drawbacks:
1) Although I doubt it would happen in this auction, occasionally an item does not receive any bids at the starting price, and the auctioneer lowers the starting bid price.
2) Let's say an item has a starting price of 200 euros and your maximum bid is 400 euros. You would be in a better position if you didn't enter the bidding until seeing how others are bidding. I believe that you would not get the item for less than what you bid, where you might have been able to had you participated live. I may be wrong on that; so that's a question that could be asked of the auction house in advance.
general info per my own experiences:
When offered the option to bid over the phone (not through eBay) you can hear what's going on, and you save some of the premium. However, if one is not fluent in French, this could be difficult.
I have always been able to get a shipping estimate from the auction house in advance, based on the heaviest item I plan to bid on. Even when I did the New Zealand auction (Haywards) the shipping was only about $45, and I got a big beach towel, shawls, etc. Maybe EMS is cheaper than Fedex.
Finally, if anyone would like to deputize me to fly to France to attend this auction and bid on your behalf, just let me know, cuz there's stuff I'd like to get for me too!!!
(dear moderators, that was absolutely just a joke)
Any further chiming in re: live auction proxy or absentee bidding would be appreciated here.