* lisp/ob-core.el (org-babel-expand-noweb-references): Change the the
  behavior of noweb expansion by replacing the prefix duplication with
  whitespace.  Fix handling of multiple noweb references on the same
  line by using temporary buffer to replace noweb references in place
  instead of collecting the intervals between references and their
  expansion text into a variable.

* doc/org.texi: Reflect the change by removing the section under
  subheading "Noweb prefix lines".

Tests pass and don't require actualization.
---
 doc/org.texi    | 24 ------------------------
 lisp/ob-core.el | 26 +++++++-------------------
 2 files changed, 7 insertions(+), 43 deletions(-)