Cold War tensions and the polio vaccine Sabin vaccine from the Soviet side. However other Soviet virologists argued that the Salk vaccine could be considered safe, since the Americans tested it on their own people. They considered that the Sabin vaccine must be potentially dangerous because the Americans did not wish to test it on their own society. The documented achievement of the Sabin-Chumakov collaboration eventually trumped the ideological differences of the Cold War. Their oral live-virus vaccine became federally licensed in 1962, and used for over three decades to help eliminate polio globally, replacing the Salk vaccine. Using these vaccines, the threat of polio remains only
His Name Is Legs (Ladies and Gentlemen) for "His Name Is Legs" included tack piano, played by Canadian musician David Foster, and a new horn arrangement, played by Scott and Chuck Findley, another member of Harrison's tour band the previous year. Scott and Findley recorded their contributions at A&M Studios over 2–3 June, with each musician overdubbing two horn parts.<ref name="Extra Texture/YouTube">George Harrison interview, "Rockweek", (retrieved 13 September 2013).</ref> The released recording begins with an introductory bass riff from Weeks, which is then joined by Foster's tack piano. Commentators note the lack of clarity in the mix, which author Elliot Huntley attributes to the "three-pronged piano attack"