I'm sorry, meerkat, this is totally wrong and must be corrected for anyone else reading it
Live Polarity of supply is tested and confirmed immediately after the dead tests,
before the installation is energised.
The reason for this is that if the DNO fella had a bad day and got it wrong, you will know before you energise your installation.
Therefore it cannot be confirmed during Zs tests or Rcd tests or with a socket tester - as this will be too late as you're already energised.
The other 'live' test that has to be performed
before energising the installation is Ze, to confirm the supply earth path.
Hope that clears things up