The trouble with one-size-fits-all recommendations is that they tend to create as many challenges as they address.

The city's medical officer of health, Dr. David McKeown, is recommending the city support reducing speed limits to 30 km/hr on all residential streets as well as having a city-wide speed limit of 40 km/hr on all other streets (with some exceptions). The recommendations are based on his report, Road to Health: Improving Walking and Cycling in Toronto.

Next Monday, the board of health will consider McKeown's report. City Council is due to consider it on May 8.

At the heart of this recommendation is pedestrian and cyclist safety.

"Pedestrians have an estimated 85 per cent chance of dying when hit by a car travelling at 50 km/hr but fatality rates decrease to less than five per cent when the car travels at 30 km/hr," the report notes.

Getting motorists to reduce their speeds in the interest of public safety is commendable, but this is too drastic a step to be across the board.

The city is not homogenous. Road networks in the city's suburban areas are far different than those downtown, for example. Traffic calming measures needed in one part of the city aren't necessarily required in another.

It is better to have a tailored approach with a mechanism that addresses specific neighbourhood needs in specific communities. Toronto's road network is diverse.

Reducing the speed limit from 50 to 40 km/hr is a reduction of 20 per cent. This automatically adds time to a commute, be it across town or across a neighbourhood. Already challenged drivers will seek new routes, breed new road rages potentially and further bring frustration to travel in Toronto.

There are plenty of elements to admire in McKeown's report. There's a useful quantification of the benefits of walking and cycling to work, in which the reductions in associated health care costs are estimated. Improving safety conditions for all who use our roads - pedestrians, cyclists, motorists and transit users - is a noble goal as is getting citizens to make healthier life choices.

The board of health, however, must be careful to not create more problems in a transportation network that is already overburdened.

Addressing specific safety challenges in specific neighbourhoods, from the ground up, seems a more sensible place to start.