What does this option in the "Configure Refresh" dialog do? I can't find any documentation on it.
How do you get to this?
Which version of Visio?
Sorry, I should have made this more clear. This is in the "configure refresh" dialog that you can get to when connected to an external data source (right-click on the data source in the "External Data" window). I'm on Visio 2013, but it's in other versions as well.
After you have bound a shape to the data, the shape will hold a local copy of that data.
You can see current shape data values if you select the shape, and open the "Shape Data" window.
So, now you can change these shape data values in two ways: by (directly) editing it using the "Shape Data" window or by refreshing the data from the source.
If this checkbox is cleared, Visio will not overwrite values that you have modified directly using "Shape Data" window, when you refresh the data from the source.
If the checkbox is set, then it will.