Was wondering though. When I am syncing files between server 1 and server 2 (dopus is on my desktop). Are the files routed through my PC or does it channel them directly using the servers' connections only?
They go through your PC. Windows doesn't provide a way to copy files directly from server to server, as far as I know.
(It can be done using other tools/protocols; e.g. Opus can do it for two FTP sites, but it's not part of the SMB protocol used by Windows network shares. At least to my knowledge. I'm not an expert on them and may be wrong here.)