At least a third of Conservatives voting against will be doing so in order to placate their constituency parties.
At least a third of Labourites voting in favour will be doing so in order to placate ... well, whom, exactly?
And the Bill itself will never reach Third Reading. Nor will this issue itself ever again be revived by any Government.
On the contrary, any future Government will do what they all do best to any inconvenient backbench initiative: ensure that it dies of sheer neglect.