You might be able to do this via a brute force method. It will still be a lot of manual labor. NOTE: I haven't tried this yet.
What if you do this:
-
Save each of your forms using the "Save as Source Files" method.
-
Take the myschema.xsd file from each, and combine them in to one, being careful that you do not have any duplicate elements.
-
Then create a new form using "Design a Form Template", and then picking "XML or Schema" and point to your combined Schema.
-
Then you can copy and paste your design of your forms into the new form **
-
** HOWEVER you will have to manually re-link all of your fields to the new schema fields, by right-clicking on the field and choosing "Change Binding".
I guess the better question is, what are you trying to achieve with the new form? Are you truly combining 12 disparate forms into one big long form (probably not a good idea) or are you combining forms with very similar data sources (i.e. mostly the same fields) and will show the variations using views?