Vaccine one of the vaccine components is more robust than the others and suppresses the growth and immune response to the other components. This phenomenon was first noted in the trivalent Sabin polio vaccine, where the amount of serotype 2 virus in the vaccine had to be reduced to stop it from interfering with the "take" of the serotype 1 and 3 viruses in the vaccine. This phenomenon has also been found to be a problem with the dengue vaccines currently being researched, where the DEN-3 serotype was found to predominate and suppress the response to DEN-1, −2 and −4 serotypes.
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"