tumill and shmooze1,
It seems both of you are upset about people carrying outside of the boro park eruv. It’s possible that those people are relying on some type of backup but non of us will ever know where it is. There will always be people who don’t know how to follow rules but that doesn’t posul the whole bp eruv.
I think david1999 did a great job explaining the whole issue about the validity of eruv but i don’t think you can blame david for not including some street into the bp eruv which he didn’t create.