There should be an option to have "Platforms obsolete each other" in the "Edit game" tab. Is there a specific reason why this box isn't checked? This should fix having any runner who submits runs with multiple platforms to only appear once in the boards. I don't really mind the board looking the way it does now, but it looks pretty weird as of now in my opinion. (I'm mainly talking to the mods since they are the only ones who can see the "Edit game" tab)
The reason it's setup this way is so that the top runs for each platform are always shown on the leaderboards.
You can check the top runs for each platform by clicking >Filter >Platform, and then click on whichever platform that your heart desires. I don't think people care to always see multiple runs by the same runner. There's a difference.
Personally I wouldn't be opposed to changing it, I'll talk it over with the other moderators.
We went ahead and set Platforms to obsolete each other for all the main-series Arkham games.
Moving forward we will be implementing a blacklist for users who violate the rules, people on this list will not be allowed to submit runs to our leaderboards. Anyone on the list will be contacted and be made aware of that, otherwise the list will remain anonymous. We won't retroactively delete runs