Making the new structure untyped shouldn't create problems, but it could make development difficult: if you have a bug in the transformer or in something related to it, you'll probably get a Seg. fault error instead of a clean "Not a sharedvar" error. The check could then be removed when the code is released.
Hmm. So far the transformation seems correct anyway; and really, the transform is quite simple and appears mathematically correct. Also, because of the way the compile-file driver is structured, it would be possible to remove/replace each individual transform.
Which reminds me, we need to have a proper error continuation too.