I remember the low-grade but odd and ambivalent excitement evinced by my parents when Fifth and Madison were made one-way avenues.  We were driving towards the East Side, probably to see the Herings (whose wonderful phone number I loveds: FI8-8888 -- FIvr 8's), probably in a cab, and I think they were anticipating the new navigation we'd be undertaking (the Herings lived a couple of blocks north of the 84th street exit of the transverse road).  Since we were going east on a one-way street anyhow, I didn't quite get what they were talking about -- most streets were one way, and I didn't have much of a sense of the difference between streets and avenues. Without thinking about it, I took their width or narrowness as local and variable, like that of a stream.  But it must have felt to them like a major change in their idea of the city they'd grown up in.  When my father and his father went to tell my grandmother, at her doctor's office on Fifth, that her elder son had been killed in action, Fifth was a two way avenue.