Just a few thoughts from the front about helping the visually impaired:
Perhaps it would help to have some "sighted guide" mobility training for the visually impaired. I am sure he and his wife can help you (if THEY know, which you can not count on..)
there is a very specific system of touch and leading communication between a visually impaired or totally blind person and their "sighted guide" for mobility purposes. This includes going through single and double doors that open in or out, narrow spaces, crowded or cluttered areas, theatre isles, steps with and without handrails, and crossing streets.
http://www.lowvision.org/orientation...ty_trainin.htm
http://www.tsbvi.edu/recc/om.htm
If you are near any of these V.A. hospitals, their mobility staff may also help you with some "hands on" information
http://www1.va.gov/blindrehab/page.cfm?pg=8
But don't assume a blinded individual will want you to grab him and push or pull them in the right direction. Nobody likes that, blind or seeing.