I shall make some progress.
Realistically, we cannot will the end of reducing tax avoidance without willing the means. The idea that, every time the Treasury needs to make a small change to a definition to clamp down on a new form of avoidance, we should have to come back with not just new statutory instruments but new primary legislation would really put sand in the wheels of the war on tax evasion and slow down our ability to tackle this serious problem.
Amendment 4 brings a more serious problem. If it is accepted, there will be people in the tax-avoidance industry rubbing their little hands together because the Opposition will have created, completely unwittingly, a huge new loophole, which will be used to abuse the system and avoid tax.