I believe that Susan is right and wrong. The order of which she speaks is right, but the passage is directed toward the offended, not the offender.

The offended is to go to the offender privately. If the offender doesn't acknowledge the wrong, then the offended brings an elder with them to confront. If there is still no aknowledgment, then the elder will bring the offense ..... and this is no small thing ..... before the church.

The whole thing is not only part of trying to set things right in the church, but also...

It's not about minor offenses -- the idea was to get the early church to not bring lawsuits against one another before the secular courts. The church was already a terrible pain in society's collective ass, and Paul, mindful of this, and mindful of how much more winsome the church would appear if it was able to settle disputes in love, and not in courts, directed this kind of settlement where possible.