Uh-huh baby?
To be fair to MPs they are not expected to be lawyers in order to make laws.
They, that is MPs, are expected to be given sound and robust advice by <cough, cough, wheeze> uk civil servants.
But an even bigger principle still is that it is acceptable to make a mistake - everyone can and usually everyone does.
And so, the matter becomes:
+ what needs to be done to put things right as in the intention of the law/act in the first place (does the wording of law/act conflict with the intention of same law/act?)
+ how to process the changes (if any) required? Another vote at the House?
+ how did the mistake or oversight arise (we operated on draft 22 of the law/act not realising it had been updated twice to draft 24?)
+ what can be done to ensure similar circumstances are not repeated?
And I'd add to those:
+ how much has the rework cost?
Reasoning: civil servants, quangos, advisors and consultants don't really mind getting paid twice or more for doing the same bit of work.
Reasoning again: MPs are a bit like the owner of a large luxury ship. They might say: take us to the Canaries! It then becomes the responsibilities of support staff to make "Take us to the Canaries" doable and practicable yes?