I wrote a reply to your questions yesterday but it evidently never showed up. So I'll just make a few suggestions.
I think you are trying to compare performance at shows that often aren't quite the same from country to country.
It's got to be more than 20 years since the Doberman standard was significantly revamped and FCI shows base breeds on the standard for the country of origin--so for Dobes that's Germany.
It also means that Dobermans from countries where cropping and docking is still allowed are not even elegible to compete in those shows.
I think you'd have to be really specific about which shows you are counting as most important. And I think it probably has more to do with the revamped standard than with the actual quality of dogs.
I do know more about AKC and CKC (and even some of the South American competitions)than I do about the European shows but it's been very difficult for the Euro dogs to be competative in AKC shows for a good many years now. A few European dogs have succeeded in being competative in both areas but very few.
So what period of time are you looking at for the FCI shows? That probably makes a difference too.
I'm not trying to compare shows, but wondering why in FCI world dog shows (I think these are the most important dog shows of FCI because it reunites the best dogs from all countries affiliated) we do not see Dobermans wining groups or BIS. I only mentioned Westminster and Crufts because they are the biggest or at least the most worldwide known dog shows from AKC and KC, and in those shows, you can see Dobermans competing at the highest levels pretty often.
This show (world dog show) can take place in countries with banned cropping and docking or in countries that allow it and it has taken place in Mexico, Brazil, Russia, Argentina, China, as well as Germany, Denmark, France, etc.. It has been carried out since 1970's, when there was no ban, but still no info about winning Dobermans. Plus the standard says that if in a coutry is allowed, dogs can be shown cropped and docked.
I couldn't find information of winning dobes neither from FCI countries that show "american style" Dobermans nor FCI countries that show "euro style" Dobermans. Who knows maybe just the judges don't like Dobermans.... but not even one in 50 years? or, which I think is the most possible reason, there is no available information on the internet. Or is it because differences between american and euro lines, taking into account that a lot of FCI countries breed american lines (all American Continent, and several Asian countries for example).
May be I'm just over thinking and should invest my time in something else (my wife votes for this)