Thanks for the link to the paper. I found it interesting. I also found it somewhat biased and amusing.
I am grateful for the part just before Section 7.1 where he lists the 5 things that determine whether a template system is push-style or pull-style. I think you would agree that only Seamstress is push-style. Everything else on CPAN (including Petal) and HTML_Tree (not on CPAN) is pull-style.
I found it amusing because section 7.1 is labeled "Pull Strategy Violates Separation" - but he never treats the topic of whether "Push Strategy Violates separation."
I dont think it can. Can you provide an example of where it does? You only have meld3, Seamstress and XMLC and StringTemplate to pick on, because those the only push-style templating systems out there.