Learned a valuable lesson the other day.
Scenario: Copy/Paste on a remote server was extremely slow. So slow it took 45 minutes to copy and paste 50 MB from one folder to another on the same server and same drive.
The Problem and Solution: In my connection profile for that server I had my C: drive checked as a local resource. I did not even remember doing this. Well even though I was not copying/pasting anything from my local computer it was routing the operation through my remote connection. Once I unchecked the C: from the local resource it was lightening fast again.