When you port forward, you set up a connection to the other computer, such that any "special" URL's in your own browser will be sent to that other computer, instead of being sent out to the rest of the internet, often through an SSH "tunnel".
For instance if I set up port forwarding on port 80, then when I type in "localhost/LOCATION" it will browse LOCATION on the other computer as though I were connected to a server on the internet.
So, if I set up an SSH tunnel to that server that links port 80 on my computer with port 80 on the server, then when I type in "localhost/LOCATION" in my Chrome browser, I get /LOCATION and the public_html folder that I've placed in LOCATION. This then lets me test out links between web pages as though I were sitting at that computer browsing.
This is particularly helpful when (say) port 80 on the server isn't publicly open, and nobody outside the organization can usually connect to the public_html folder that I connected to after setting up the SSH tunnel.
For instance, in PuTTY, I would set something like this... I attached the image. Anyway, I can't add that option to the temporary PuTTY connection that WinSCP opens.
Although it's always possible that your suggestion would fix my problem, but that I don't understand enough about what you were saying to implement it.