[eluser]sophistry[/eluser]
using {{url}} is better, but still forces a "link" between the actual filename and the helper function. anyone working in a template shouldn't have to care or know what file the helper function sits in. the function names have to be unique anyway so adding that {{url}} seems just for lazy loading... but, you could do the same thing by figuring out which functions the template wanted then figuring out which file to load - that could all happen out of the template in the loader code.
also, one observation about Smarty template syntax: it centers on the variable and then an operation on that variable which is how english works: we say "the programmer codes." not "codes the programmer."
function-centric templates (as opposed to variable-centric) force you to think about the verb first.
btw, well done stirring the pot here - your work is undeniably fruitful!
cheers.