The workweek alteration experiment should be carried to its logical conclusion. Twelve hour (or longer) workdays would be ideal. That way the employees could commute in two hours earlier than everyone else and leave two hours later. This would cut down their commute times because there would be less traffic on the roads at 6 a.m. and 7 p.m. If we further extend the workweek to be every day instead of just five days a week, further improvements could be realized. Mondays and Fridays are always the least productive days for employees. At the beginning of the week, they need to get back into the work flow after time off. At the end of the week, they're in their "getting ready for the weekend" mode. If we eliminate this gap of non-work, productivity will go up.
It's high time we changed our strict 9-5 M-F work schedule. Playing around with increasing those hours and days could realize lots of benefits for your company.