I had a co-worker who live in a FLW house near Atlanta. It was 80% glass windows, so he relied on an alarm system because door locks were basically useless to keep anyone out who wanted in. I always was uncomfortable in that place.
Exactly. When I was a teenager I lived in a Chicago-area house based on FLW design. It also had huge expanses of glass and a nearly flat roof. The roof was, of course, a disaster during snowy Chicago winters. Annoying enough having to shovel the driveway every ten minutes in winter, but to have to get up there and do the roof too absolutely stank! The glass and high ceilings made the place harder to heat than a corn crib, and we were always chilly in the winter (which in Chicago lasts for nine months). With that open floor plan, there was no privacy: if someone took a phone call or listened to the stereo or watched TV, EVERYONE had to listen, too. There was no privacy from the outside world, either, for buying curtains to cover those expanses of glass would have bankrupted my folks.
But living in that house did have one beneficial effect: it turned me into a gun-lover. For I too found out, in those pre-alarm system days, that when somebody wants to come in through your twenty-five-foot-wide front window, a lock on the door is not going to stop him. Standing on the other side of a twelve-foot-tall sheet of glass while holding a .38 does.
In any case I will never live in a contemporary house again. We've been building houses in pretty much the same way in this country for the past 350 years, and there are some very good reasons for that.