In one application that I made, we did a lot of insert into the database. At first, the performance was really slow. The network usage between the server and the application was minimal.
We accelerated the inserts by using parameterized insert. This gave us some performance improvement, but it was still slow.
As each connection is slow, we created many connection (40 connection) and inserted all the data using all those connection at the same time. This increased performance a lot more and we consider it fast enough now.