The British weaknesses is a subject studied by historians.
But how was it possible if the Britain's military was the best in the world. Theirs soldiers were well equipped, well disciplined, well paid and well and well feed.
However it was a situation which they had to confront. It does refer the British fought a war far from home. Military orders, troops and supplies sometimes took months to reach their destinations. It means that the British had an extremely difficult objective.
In summary, the geographic vastness of the colonies proved a hindrance to the british effort. Despite occupying every mayor city, the British remained as at a disadvantage.
It was the "First Continental Congress" that was formed after the passage of the Coercive (Intolerable) Acts, since these Acts represented somewhat of a "final straw" in terms of royal mistreatment of the colonists.
In Article II, Section 3 of the Constitution, it states that the president has the power to call a Special Session. The reason why he rarely has to call a Special Session is because of the changes made by the 20th Amendment. Prior to the ratification of the 20th Amendment, Congress convened in December and typically adjourned in March. But after the ratification, Congress convenes on January 3 and typically does not adjourn until late in the year. So, the president rarely has to call Congress into session because Congress isn't generally out of session long.