Was an Amputee Gymnast in the 1904 St. Louis Games as Great an Olympian as Michael Phelps?

Tim Dahlberg, a national sports columnist for The Associated Press, agrees that Michael Phelps is certainly the greatest Olympic swimmer ever, but comparing him to dominant athletes in other events and in other eras is more difficult, he says. Carl Lewis, for example, didn't have as many opportunities to medal, but he was still the best in the 100m, the 200m, and the long jump for four Games.

Dahlberg proposes another candidate for best ever: George Eyser, who competed here in St. Louis in the 1904 Olympic Games. "Eyser won six medals in 1904 in gymnastics, despite a left leg made of wood after his original one was run over by a train."

Wikipedia includes this brief entry on Eyser:

George Eyser (born 1871, date of death unknown) was an American gymnast who competed in the 1904 Summer Olympics, earning six medals, including three gold. Eyser competed with a wooden prosthesis for a left leg[1], having lost his real leg after being run over by a train[2]. He is the only person with an artificial leg to have competed at the Olympic Games to date, although Natalie du Toit, an amputee South African swimmer, has qualified to take part in the 2008 Summer Olympics in Beijing.[3]