gavra-at-work,thanks for the mature thread !!
May I say at the outset that ,in past times in cities throughout europe, there was never a problem because there was not one street that was sixteen amos wide. If you ever visit Europe and go to the old centers, you will see that the streets were always narrow- never wide (like the Old city in Yerushalaim).Also, not one street was ever “mefulosh”-going straigth across the city -or at least having both entrance and exit lined up. The problem arose in the large squares and in the new cities. This is where the hetter of the 600,000 arose- if the other freeing details were absent. The later Poskin througout Europe took the view that we need “shshim ribui” to make a full reshus horabim and every city in europe had an eiruv,including vilna, i think! until the twentieth century, there was barely a city in the world that had six hundred thousand together- (remember, they must pass in one day!)and so ,virtually every city had an eiruv. Today, in cities like new york and london, this problem has arisen. By and large,however, it seems that the majority of later poskim held the view that you need six hundred thousand. BTW- there were many,many rabbonim in Warsaw-not only R’menachen Zembe HYD who, by the way, did not occupy a pulpit.
Today, of course,