Hi there - a very good and healthy debate about a very complicated issue. What comes first - the instability or the muscle imbalance. The SI-joint function is depending on a great amount of variables - breathing (diaphragm/psoas-connection) - could be an ascending problem, or a descending problem - stress from organs - or a combination of them all. Complex !!! Handling of the issue is therefore not an"easy fix" - it's lifestyle - it's like going on a diet - it only helps when you're on it. You have to continue the rest of your life with the exercises - the right exercises !!! It is about muscle-imbalance - stretcing and strengthening - an occational adjustment (ME or direct) when done the right way is not the issue. CORE strength and stabilization is the key - work work work. Good luck.