It's not necessary that the file 'include.acl' contains the lines...
# start of ...
...
# end of ...
...because these lines are automatically added when saving through the
GUI => 'proxy.cgi', lines ~3602ff.
yeah, good catch. The wiki refers to what will be in squid.conf, so technically the text was correct, however it was really confusing too. I did add a sentence to remove the confusion. Please let me know if you don't find it clear enough or incorrect.