Remove and Reinstall Python on Mac -- Can I trust these old references?
So, I ended up removing all python installations, and reinstalling things via Homebrew.  


which python ---> /Library/Frameworks/Python.framework/Versions/2.7/bin/python
Delete the entire Python.framework directory from /Library/Frameworks.
which python3 ---> /usr/local/bin/python3  Delete the entire python3 directory.
I was a bit nervous about the symlinks.  I initially renamed the ones that were obviously going to cause me trouble. It turns out that was unnecessary.  Instead, just use:

$ brew doctor
Warning: Broken symlinks were found. Remove them with 'brew prune':
  /usr/local/bin/python-32
  /usr/local/bin/python2-32
  /usr/local/bin/python2.7-32
  /usr/local/bin/python2_DNU
  /usr/local/bin/python_DNU
  /usr/local/bin/pythonw-32
  /usr/local/bin/pythonw2-32
  /usr/local/bin/pythonw2.7-32


So, brew prune (or brew cleanup --prune in newer versions of Homebrew) worked perfectly. It removed all of the above symlinks.  
Reinstall python and python3 via homebrew.  All done. 


At no time did I touch the python installation located within the /System folder.  

Oh, and to be clear.  The answer to the original question is 


  Yes, you can trust the old references, as written! That guidance is still valid.