A person who goes out with a coral ring and hides it from the eyes of R. Yehudah HaNasi on Shabbat, so as not to be obviously carrying on Shabbat -- that kind of respect for Shabbat allows that same person to renounce his ownership rights within a courtyard, and enabling others to carry. [What's What: Mumar.] Brazen desecration of Shabbat becomes the measuring stick for the sinner - based on whether that violation indicates a willingness to transgress everything else, or whether each sin is its own. But if the one sin is idolatry, then there's no longer a dispute, because it fundamentally nullifies everything else. Granted, these days, we relate to this kind of transgression and those who transgress differently. Also - back to renouncing one's rights: one who forgot to participate in the courtyard's eruv - what are the parameters of where you aren't allowed to carry? Or if people gave away their rights to enable the person who forgot as well, then that person would be allowed to carry, and they would not. But if two residents forgot to participate, they each nix the carrying of the other. When does the eruv need to be made (or discovered to have been forgotten)? Is the issue close to Shabbat, or earlier on Friday? Also, how does the renouncing of your rights make your own house off-limits?! Renouncing the rights to the courtyard only is the better (and more obvious) approach. What about a guest and the eruv... we don't make the guest buy into the eruv. So the person who renounces fundamentally becomes the first of the others on the courtyard. Which speaks to the apostate and the reclusion from the cooperative.