If you are still interested in this, I believe it is possible to merge from
a Sharepoint list using a linked table in Access, but it's tricky to set up.

However, to do that, you need Access on your system and you need to link to
the relevant Sharepoint list(s). Also, you will probably find that Word does
not "see" the linked tables when you try to link to the Access database, but
I believe it will correctly use them if you issue the correct SQL in a VBA
OpenDataSource command.

I believe it should be possible to create an Access .mdb and the appropriate
linked tables programmatically using ADOX (even if you haven't got Access on
your system) but even that is tricky because
a. you need to find out the "internal" name of the Sharepoint list in order
to create the linked table. There are apparently ways to do that
programmatically but I haven't explored them yet. The simplest way is to use
Access to create the link and examine the resulting table's properties, but
of course that means you have to have Access (although you could probably
distribute the resulting .mdb to non-Access systems)
b. The correct VBA to do this still eludes me

Peter Jamieson