Just watched on youtube LD and LXR playing XD in CSBL. They played terribly - just total out of sync. So 2 Olympics Gold single players playing XD doesn't mean they will dominate.
Yeah, watched it and couldn't have agreed more with you. From the gameplay itself, i really can't spot that the two are actually olympic singles champions in their respective categories. So the next time, u wanna beat ld, ask him for a xd game..lol
Many players play both as juniors and then specialize soon after graduating to senior. Korea has so many current doubles players who have been singles winners or runners-up at the German Junior, for example: Shin Baek Cheol, Kang Ji Wook, Choi Sol Kyu, Choi Hye In, Eom Hye Won, Lee So Hee. The Koreans hardly ever look back and never play singles again except in domestic events or when their team is trying to lose a team tie (Lee Yong Dae's singles foray in 2008). Misaki Matsutomo began focussing on doubles shortly after being WJC runner-up in 2010.
Sapsiree, who was also born in 1992, kept playing both until just last year and is thus an example of another norm, which is for players to do a one-time switch at some later point in their career. That is usually from singles to doubles. In addition to Fischer Nielsen, mentioned above, we have seen recently Shoji Sato, Przemyslaw Wacha, and Mohd Hafiz Hashim. I'm not sure I've ever seen someone completely specialize in doubles past the age of 20, then switch to singles, reaching the top 30 in both.
Obviously, players on teams with more depth tend to be more likely to specialize so you would expect to find more singles/doubles overlap in Canada, Peru, Australia, etc. There was a lot of double duty at the recent European Women's Team Championships, even in the later rounds, and that is almost unheard-of for top Asian Uber Cup teams.
If you look at the top 30, it seems that most who have excelled in both are European women. craigandy mentioned Petya Nedeltcheva. Mia Audina and Juliane Schenk are other examples. As for men, Ivanov, pointed out by SpeedyJT above, is a rare example.
As laonong points out, there are certainly examples of players winning big titles in both singles and doubles. Most of the Koreans who have done it won singles titles, switched to doubles and then won doubles titles and they were all women: Hwang Sun Ae, Kim Yun Ja, and Ra Kyung Min. If you go back before the Koreans and Chinese entered the picture, you are before badminton was in the Olympics and before the Worlds existed but you have lots of examples of singles/doubles champions at the All England, even in the same year. I think the last triple at the All England was Gillian Gilks in 1976.
The training program, type of shots, footwork and movement, even racquet type and choice of string tensions for singles and doubles have diverged significantly since the rally point system took effect.
I'd say there is absolutely no way for a top singles player to also be a top doubles exponent or vice versa.