The ad is inspiring, but it doesn't tell a even tiny fraction of the real story behind the NYC marathon finish line.
I've been a member of the Achilles Track Club, a NY City based club for "disabled" runners, since about 1992. Though I've never run a marathon, I've run literally hundreds of shorter distance races up to about 15Km. ATC was started by a guy who had a prosthetic leg and wanted to give the world a message about disabilities.
ATC members who have run the NYC marathon are survivors of just about any disease or loss of body functionality that you could ever imagine. There are wheelchair athletes, blind runners and people who "run" on crutches and take upwards of 18 hours to finish. When I first joined I thought I was such a special case because I had an artificial valve, but soon realized that my limitations paled to a dull gray in comparison to many of the others.