Hi Scott,
Just like you, I've been dealing with the same design inconsintency. I always thought that one can have access to the TreeView.Node ToolTipText. Unfortunately, no such thing. As you described, the so called, TreeView.Node.ToolTipText is only used to display a node value wider that the row it sits on.
My only work-around was to provide this value in a StatusBar.Panel. Still this meant that a user would have to look elsewhere for the information.
I hope they add this capability into the ActiveX control, as well as a TreeView.BackColor property.
Best wishes
Juan