For 2007 the Standard Rate Cut-off Point (SRCOP) is €34,000 single. €68,000 married with maximum of €43,000 - €25,000 transfer of SRCOP. So theres a maximum of €34,000 to €43,000 transfer available from single & 2 incomes to married and 2 incomes or €9,000 potentially which could be taxed at 20% rather than 41% which is €1,890 in tax pa or €157.50 pm. All depending on the pay scenarios. So yes, you're fairly on the ball with the amount there.
As to the whys and wherefores of the law, been there, done that, pirated the DVD, etc.etc.etc.