The first article has to do with Great Britain and how their system has no written constitution that sets a consistency for a nation to follow. A constitution is a system of fundamental laws and principles that prescribes the nature, functions, and limits of a government. They are fundamentally flawed because they date and the phrasing/ meaning of the law becomes open to interpretation. For example, the American constitution was written over 200 years ago just after the end of the war of independence and the written constitution was a response, so there could not be a autocratic form of government. However it does not allow for the evolution and development of the initial ideas. Much like the Irish constitution where the government put in clauses so that abortion can never be legalized. .
Fascism and communism took root in countries in the 20th century and have been responsible for the murder of millions. Where are the most obvious example of these two ideologies, fascism in Germany and communism in Russia both of these country's had written constitutions. It doesn't matter what rules or restrictions you put on a government whose whole ideology is extremist, if they want something done they will do it no matter how many laws they break. The problem is not a tyrannical government but a government ruled by a tyrant. In the 20th century a written constitution was not protection from a tyrannical government but because of tiny proportion of countries that don't have written constitutions it's impossible to say that it is in fact the protection from a tyrant.
One of the futures of a written constitution is they often separate the three arms of government, the executive the judiciary and the legislature. This being a feature of the written constitution may be interpreted as a strong protection against tyrannical government. However, as noted above there's no protection from fascism in Germany and communism in Russia.
