A wise man once said: "On a '96 and newer 4R70W's, you can do all the manual 1-2 and 2-1 shifts you want and not hurt anything......stay away from excessive manual 4-2's on all transmissions older the 1998."
So you're probably right about that one.
If you want to learn everything you need to know about your 4R70W, check out
this link and click on "Ford OD Transmissions 101 - Jerry's mod."