I pretty much feel as you do and I think I've read the same research. I'm about compassion as well and don't think you can apply a few hard and fast rules to every addict. Not every 'patient' reacts to their medication in the same way. Some need more, some less, some need a different kind altogether.
To me codependency is a term that has been distorted and as someone whose family is in latin american, I can tell you that everyone in latin america would be seen as codependent! Not to mention the social stigmas that bring about 'shame' in families. But I take away the general message which is you can only work on yourself and if you expend so much mental and emotional energy on the addict, it doesn't get the addict any closer to treatment and leaves you depleted.
There is nothing anyone can do to change the addict into not being an addict. There is no cure, only treatment and management. But ultimately wanting to manage their illness is an internal struggle within the addict, not one that loved ones or friends can control. Sometimes they do more harm than good actually. It is about boundaries and knowing when to show compassion and when to take care of yourself first. Sadly all the emotions that go along with watching a loved one do this to themselves actually break apart the very families that can be a source of support. Hard to be supportive of someone if they are threatening you with violence or stealing money from your kids.
So that is where compassion has its limits. I can see both sides to the debate.