Asking this question here rather than on the FG forum as I want a broader viewpoint in the answers.
What is the attraction of a fixed gear bike? It seems impractical in hilly terrain, including many cities where they seem to be quite common. How much of it is practicality and how much a current fashion? The FG practically disappeared as a bike type, except for track racing use, from the time of the development of the freewheel about 1898 until it's revival in popularity in the last 10 years or so. The histories indicate that it disappeared due to the freewheel equipped bike being more user friendly. So are the current riders all masochists or what?
To me a freewheel equipped bike, for single speed, or a geared hub, seems more practical for a person who wants a non derailleur geartrain. BTW I have a FG rear wheel for one track style frame and have tried it out in the past but now that I am 60+ I want to spare the knees. It therefore has a geared hub wheel installed for normal use.