Agree with Liam on this. Answer the question asked. In this case it is an in depth answer on the "disadvantages of an uncodified constitution". You should be able to state each disadvantage in one sentence and then go on to explain in depth each disadvantage with many sentences. You need to show you understand why each point is a disadvantage.
For example:
An unacceptable amount of power could drift towards the executive or prime minister.
Liberals have argued that lack of clarity about the powers of the PM, executive, legislature and judiciary has led to power being concentrated in the PM and the executive. If powers of the institutions of government were clearly stated it would be far more difficult for power to shift from one place to another. Any shift of power would require a stated constitutional change. Without codification, power can shift over time towards the PM with the passing of one law then another.
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