Ahh, I see that's written by the ANTLR/StringTemplate guy. I never read that paper, but the docs for his StringTemplate were a big part of what convinced me that template engines shouldn't try to be full-fledged imperative programming languages.
I've done web development for a chunk of my career and I have to agree. To me, there should be a clean separation between code and templates. Templates that have looping in them are garbage to me as now you have logic in two different places.
The best templating solution that I've seen is Template::Recall for Perl (http://search.cpan.org/~gilad/Template-Recall-0.15/lib/Template/Recall.pm)
In this case, there is no logic in the template. You "render" the different parts of the template as needed and you have full control within your code. To me, something like this should be part of the standard library as it would make outputting formatted text much easier in those cases where there is a standardized format, like XML or HTML.
Casey
