I'm sorry to say that I have never actually used Techwriter on RO. However, there exists a very solid and well tested chain of tools to convert between .tex and .latex. Would it worthwhile to port these tools to RO?
Perhaps Techwriter could take inspiration from LyX [link] in terms of support for external tools? In LyX it is possible to export to or import from pretty much any type of document by specifying the appropriate converter tool.
One advantage of a modular approach such as this is that it enables support for diverse output formats such as man pages and XHTML for example.
Having said that, I'm far from being a LaTeX guru. Are there any special issues that I am not aware of? Is there any vital information that would be missing from a .tex to LaTeX translation, as opposed to native support?