Charles II decided that his brother would be his heir.

Parliament decided otherwise and replaced James with William of Orange in the Glorious Revolution of 1688.

Parliament rules supreme.

It’s why they ceremonially slam the door of the House of Commons in the face of Black Rod every State Opening of Parliament.

It’s a clear reminder of where power ultimately resides.

Our constitution looks “lumpy” because it’s evolved and not designed. Rather like the Common Law.