You, again, are so right. Rules assure unity, if not uniformity. Rules address commonality of goals, if not commonality of tactics. 

 My issue is the rigid insistence that non-conformity with rules and canons constitutes--each and every time--SIN.  

This approach homogenizes  essentials with non-essentials, to me a "sin" in and of itself. And,  to me, it dilutes the concept of sin---making sin anything that doesn't conform with the legalisms of the day...or the era.

We have cried "wolf" so many times when it comes to sin that we have lazily  failed to elevate core essentials from the non-essentials of our faith. We have downgraded Christ to former head of the CDF. 

Maybe its something the Catholic Right and the Left can agree on: we need to focus on condemning the few (circa10?) true sins, freely admitting that there is indeed sin in the world.

But Catholics are guilty of "sin creep," having over-used, misused, and mega-legalized what sin is. Indeed, we've actually created sins.