Dang it. No, it's not.
in reply to Re^2: Five Ways to Reverse a String of Words (C#, Perl 5, Perl6, Ruby, Haskell)
in thread Five Ways to Reverse a String of Words (C#, Perl 5, Perl 6, Ruby, Haskell)
This isn't a problem with R, it is a problem with me not thinking. Not only did I forget the split/join, the sort function I originally used only worked because my test case happened to be in alphabetical order. I have updated the original post with functioning code.
My apologies to all of you who incorporated the broken code into your mission-critical systems.