I think the original posters and those who continue to raise the issue of lack of additional AWDs or reduction in their time standard is - these restrictions are often created because of a lack of space logistically, or lack of permission from the cities and towns to conduct an event that essentially shuts them down for its duration.
One of the biggest impediment to more athletes (either able-bodied or AWD) is the lack of space in Hopkinton for staging. There is little to no room in Hopkinton Green. Anyone who has run the marathon itself (unless you're sub 2:40) will probably remember being packed in for at least the first 6 miles. Things do not open up until you're running by the Natick train stations.
Limiting the field size is not done to punish athletes, it's done because of the logistical challenges associated with staging all of these 30,000 runners, thousands of volunteers and other staffers, the AWDs - in a town that has a population of less than 15,000 people.
Also, it's done because the cities and towns will not allow them to have more because that can impact the amount of time the roads must be closed off. This same reason can apply to the AWD time cutoff. Check with the cities and towns about what they have asked the BAA for.
The race runs along the main road in Hopkinton and Ashland. They're shut down for quite a while. The course runs along 135, which is not the most heavily traveled road in Framingham and Natick - but it does completely cut off the north side from the south and runs through the Natick town center. In Wellesley, this is the main town road and cuts through its town center. Newton, not the absolute main road, but it's on one that slices the city in half. Boston and Brookline, same thing.
The BAA has to ask permission to close off the roads entirely to traffic for a period of time. This isn't some small road race where a cop can stand at a street intersection and wave a few cars through when there's an opening in the field. These roads are completely closed and as a result, cities and towns are generally closed too. If you allow AWDs to participate for 8 hours, that means you are closing down the roads earlier (and for more time), or you are opening the possibility of a number of AWDs mixing in with able-bodied runners .... on tight, compact roads. Which could result in safety issues.
This isn't discrimination, which is disparate treatment (or impact), usually on a protected group. This is the BAA doing the best it can with the space that it has to work in, and the permissions granted from the cities and towns to create the most all-inclusive event possible.
