I just tested this theory using Speedtest.net.
With just my wireless aircard, I obtained these results:
DOWNLOAD SPEED: 364 KBPS
UPLOAD SPEED: 95 KBPS
I then did exactly what Steve said to do - connected to a Flying J wireless internet with my wireless aircard still running (which he is correct - my computer said I was connected). I then obtained these results from Speedtest.net:
DOWNLOAD SPEED: 462 KBPS
UPLOAD SPEED: 106 KBPS
I then shut off the Flying J connection, and retested:
DOWNLOAD SPEED: 376 KBPS
UPLOAD SPEED: 101 KBPS
Not a huge change, but a change nonetheless. I then tried it again with both Flying J and my wireless internet connected:
DOWNLOAD SPEED: 410 KBPS
UPLOAD SPEED: 114 KBPS
I then disconnected Flying J, and retested:
DOWNLOAD SPEED: 432 KBPS
UPLOAD SPEED: 114 KBPS
I'm questioning the legitimacy of this because, while I am "technically" connected to the Flying J signal, I am only connected on the local level (not local and internet). My connection with them ends at their server inside the building. I think any change is being caused by fluctuations in the wireless signal. While this would work on a free network (like a hotel that has WiFi), I don't see how this is doing anything on a closed network (like truckstop WiFi).
It seems to me this doesn't really do anything at all with a truckstop connection.