One of the things that's going to come up with a compressed work week is that your going to elongate the days, I presume. Then people are going to work longer days, which is going to impact both their family life and their work life. They'll be required to work an additional three or four hours every day in order to make up the day that's been compressed.
I now work a compressed week, but it can be very difficult for people with child care. Most child-care facilities operate during daylight hours only, and most of them want the children cleared out by five, or at the latest by six o'clock in the afternoon. If you're a younger family with younger kids who are in day care, that's where we would end up going.
The other issue, of course, is the additional cost to the employer through the collective agreement, because of overtime, shift premiums, and so on.