Were all the american grievances really justified, or were the british actually being more reasonable than most americans have traditionally believed?

Personally, i do believed that the British was among the most reasonable empire that ever created colonies. Because they treated their colonies as business partners rather than country-slaves.
If you pay attention, ex-british colonies tend to be way more advanced compared to colonies from other countries
For example, United States which dominated north America, Singapore and Malaysia which dominated South East Asia, India which dominated South Asia, South Africa which dominated the whole African Region, etc.

You can drink laxative, or  do this exercise when you are sitting in the bathroom on the toilet. to relieve  constipation  fast or in about 1 minute, pinch your nose after your usual exhalation. start holding your breath. but do not mouth breath during this just hold your breath.