Thanks for the link to the other thread and to the Draft Environmental Impact Statement. It looks like we have 11 more days to submit comments on the decision making process. I would encourage others to submit their input using this site: (
http://parkplanning.nps.gov/document.cfm?parkID=65&projectID=22633&documentID=69426.
After reading the EIS here is my take on the situation:
Currently, backcountry bicycle use is limited to park roads open to motorized vehicles which means the Arizona Trail North Rim segment is off limits to bicycles, as are the other trails in the park. No day use permit is currently needed to walk from rim to rim. These current practices are designated as Alternative A in the EIS.
Under the other three Alternatives (Alternative B is the Park Service's preferred alternative), bicycles would be allowed on the Arizona Trail North Rim segment, the Basin Road (Point Sublime), Kanabownits, and Swamp and Fire Point Roads would remain open to use by cyclists, however a permit would be required for rim-to-rim hikers. If it is anything like getting a backcountry permit for overnight hiking in the canyon, the process is cumbersome. For through-bikers and those (unofficially!) racing the AZT this would be a big deal, especially if the rim-to-rim runners have already snatched up all the permits allocated for the day.
The EIS make no mention of the current practice of the Park Service allowing a bicycle to be carried on your back through the canyon. Maybe it is better not to bring up this topic during this process.