You're completely right, I wasn't thinking about that! 

PTP losses aren't tracked on 8582 because the losses from a PTP can only offset future gains from the same PTP (not pooled with other passive losses).  You can still enter the past losses on the "Passive C/O" tab, but as long as you checked the "Publicly traded partnership" box for the partnership info, it won't put it on the 8582.