BCL is heavily disadvantaged at Doubles. Because of his height, he will find it hard to drive.
Look at Jens Eriksen, he is even taller than BCL but he can do well in the front.
I think TH would be the best double player amongst all 4 of them with his drives, and LCW and LD is about the same in terms of attacking power. BCL, well he is a control player, so might not be a very good idea for him to play doubles.
In the practice, TH plays alot of double...in recent practice, I saw TH paring with Candra Wijaya, I believe they lost to Joko Riyadi/Ahsan ( they did not playfull set...mostly 11 points with betting).....but other occasions, TH won also.......
In serious note, TH may play double once his single is over.