Can end users of a dashboard post comments on a dashboard

Can end users of a dashboard post comments on a dashboard that others can see? For example, while switching through months of a dashboard, executives could post explanations/comments to highlight business activities. The end users would not be dashboard developers, they would only be end users viewing the dashboard from Infoview.

My assumption is that there would have to be a method to read/write to a database from Xcelsius, does this capability exist?