BRE
There are two reasons why LH preferred the A340 to the A330. The first, and biggest, is that the A330 Airbus will sell you today is far removed from the aircraft available around the year 2000. Considerable performance improvements, paired with ever increasing MTOW figures, has enabled the A330 of today to perform routes the A330 of 2000 vintage couldn't. Secondly, the senior air heads at Lufty has had a historic dislike of crossing oceans with anything less than 3 engines. That was one of the reasons they nixed the 777 and went for the A340 instead. But even the wrinkly old LH skippers eventually found that further resistance would be futile, and now LH have joined the group that are crossing oceans on 2 donks.