"No taxation without representation"

It seems like, if taking the text book cause of the American revolution by face value, all King George had to do was invite some representatives from the 13 colonies and made them sit in tax meetings. Since colonists were paying lower taxes than people in Britain mainland anyways, as long as the formality of representation was handled, then the colonies would not have fought for independence and accepted their tax duties?

This doesn't make much sense for me, since King George can't possibly be that incompetent right ? It seems fairly easy for King George to keep all the colonies...