Originally Posted by rbAA
The train segment must be booked at the time you book your AA flights, through AA or similar, and must have AA flight number. Thalys to BRU is 250 miles per segment while SNCF is 500, to Lyon etc. They do not give you much of a selection and no flexibilty, as you can not change or apply to another train/date/time, in my experience.
I do JFK-CDG-LYS (on the AA TGV codeshare) with some degree of frequency, and I agree that the train departures offered are not the best connection with the arrival of the flight. However, I have never had a problem going to the TGV station at CDG and successfully requesting a change to the next available TGV departure.