Wirelessly posted (BlackBerry8530/5.0.0.1030 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)

BAEC now charges for each flight flown, based on distance and class of service of each flight. DFW-LAX costs 10,000 Avios one way in Coach, or 30,000 Avios one way in First Class. (AA does not offer Business Class on the DFW-LAX route.)

TXL-LHR-DFW-LAX will always cost more Avios than TXL-LHR-LAX.

(If you were to redeem AAdvantage miles rather than Avios, AA would charge you 62,500 AAdvantage miles for a First Class award from TXL to LAX, regardless of whether you flew TXL-LHR-DFW-LAX, or just TXL-LHR-LAX. AA still uses a zone-based award system; BA no longer does.)