If, for example, you have your forms saved to a SharePoint site, you can certainly write code to pull up a list of saved forms... the user could select which one they want, and then have code use that form's data to populate the field in the currently open form.
There'd be a bit of code-writing to make it happen, but you could do this.
The other option is to create another form, based off the same schema, but repeating--and use that as a source XML file to do the same thing. Then you only have to maintain a single source XML file -- but this could get very big very fast too.
Essentially, you'll have to write code to do what you want to do, but it is possible to do it.