No, I wrote that for creating/loading of new data.....not for editing existing data.
For editing existing data, you just need to grant the Logins sufficient permissions either on the database (db_reader, db_writer) or on individual data (ArcCatalog privileges)
However, to create/load new data using the DBO schema----you'll have to grant sysadmin to the other users.
That is the reason, its advisable to create a common Login for loading/creating new data into the sde gdb and I'll suggest you the same, unless you specifically need to load it with DBO-Schema