I used to avoid this by `(setq org-babel-use-quick-and-dirty-noweb-expansion t)'.
This illustrates the issue: #+begin_src org ,* abc ,#+begin_src R :comment (message "running on empty") ,#+end_src ,#+begin_src R :noweb yes 1 ,#+end_src #+end_src The irrelevant, unnamed, empty src block its consulted via org-babel-get-src-block-info. This runs the (message ...) expression. Not much of a problem here, but I sometimes have a src block in my buffer that is a work-in-progress and has a header arg that calls a function I would not ordinarily have loaded. When noweb does its thing, it chokes on the lack of a function. Chuck
