Recently I saw changes, and contacted the author about it. He creates objects that are absolutely impossible in that area. In a marsh he redefines canals as roads, even motorways; creates bus routes in a lake, ferries that have no connection with a road, etc.
His answer was, that he knows it is not correct, but he works on a project in the Transport layer and needs “real data” for his project. So he just creates his “real data” where he thinks it is correct. In 14 days he made about 300 changes and I still have to find something realistic. He “promised” that he will delete all experiments afte his project ha finished.
I cannot agree with such behaviour, but I don’t know if there is a way to stop or block him. I only delete each modification, of which I see it is destroying the map for other users and for those that download data for own applications.
contact DWG data@osmfoundation.org
tell him your problem, adding some commented changesets (or did you contact him per mail?)
and ask them for help. they can block the user and may be they’ll revert all his changes.