wifi vs USB for Link with classic

So it used to be that when I plugged in my Q10 to my Win 7 computer via the USB cable, link would fire up and there the device would be in the list inside Link. I could back it up and swap files etc.
My new Classic only seems to link via the wifi. And of course I unchecked the box in Link saying turn on wifi, and now I can no longer connect the phone to the computer even after I've turned on Wifi on both and they are on the same network.
This Link thing has always been just shy of voodoo. Why is it so hit an miss? i can see the device in the system devices list in windows, why can't Link see it? (both have the latest software on them)

If you take brookie229's advice from your other thread, and remove BlackBerry Link, Blend, and all BlackBerry drivers from your computer, then this question will be fixed as well :)
http://forums.crackberry.com/showthread.php?p=12427706

Posted via CB10

Well its sort of fixed it and yes those instructions are what I would normally do. It did take a few attempts though. I can now see the device in the Link and Blend software but only if I have wifi on. So while it says connect with USB cable, unless that wifi is on inside the device, no connection to link or blend appears - that says to me that the data is not traveling through the cable.