All this discussion about the safety aspects of toeclip overlap compels me to share my experiences/opinions on the subject. First let's make a distinction between a fixed gear vs freewheel bike and a track vs road bike.
A Track Bike w/fixed gear is a wonder to behold in many ways beginning with it's minimal number of pieces, the efficiency of the frame design and the lightness of the wheels. It is thrilling to ride and the closest thing to "man and machine becoming one" that one will ever experience...on the track. The fact that it has only one gear, no brakes and toe overlap presents no concern or problems. Once removed from it's intended environment and purpose, it begins to diminish in performing necessary functions much the same way that a F-1 or an Indianapolis 500 race car would if it were used for commuting or running errands to the grocery store. Most people would find it either laughable or criminal to do to a thoroughbred. My feelings are similar concerning track bikes. They're wonderful to build, look at, and ride...on the track. Take that bike out on the road and very soon the wheels become trash because the lightweight sewups, rims and spokes that were designed for optimum performance on the track, fall victim to glass, potholes and uneven road surfaces, none of which are found on the track. The single gear, again optimized for each particular track and event becomes a limiting factor on the road. Most of us who love to climb hills wouldn't choose a single geared bike. That doesn't make us less as riders. Descending steep hills and winding roads is thrilling enough on an Italian road bike with it's stiff frame and steep head angles that tend to induce speed wobbles but a track bike with even steeper angles AND toe overlap AND fixed gearing AND fragile wheels/tires in the same situation is not what I would call fun.
A track bike with a set of road rims/tires and at least one brake becomes more useable on the road but the fixed gear/toe overlap still presents a problem when trying to navigate tight corners even at slow speeds. Put a freewheel on that bike and the overlap becomes less of a problem.
So now we've desecrated our track bike almost to the point where it would make more sence to take a road bike and strip off all the gears and make it a single speed freewheel bike or a fixed gear bike with or without one or two brakes. This bike is what is most often seen in many cities in the hands of bike messengers and young urban heros. The road angles, wheelbases, and lack of toe overlap make this a much tamer creature to ride on the streets. Many of the current single speed bikes being built are wonderful machines though I still maintain, too limited in their range due to their lack of multiple gearing for my taste.
As one who rides 20-50 miles every weekday for transportation and weekend recreation rides either on the roads or trails in the mountains in and surrounding the San Francicso bay area and formerly rode at the velodrome in San Jose nearby, I have and love to ride all kinds of bicycles. As a result, my views on bicycles are fairly broad and I rarely condemn anyone's opinions of cycling. But when it comes to riding a pure bred track bike on the roads (and hills), I must admit, I think there's a better way to have fun.
Bruce Schrader San Francisco
===== "Not all those that wander are lost." -J.R.R. Tolkien (1892-1973)