Quote from
http://statutes.agc.gov.sg/Renunciation of citizenship128. —(1) Any citizen of Singapore of or over the age of 21 years and of sound mind who is also or is about to become a citizen of another country may renounce his citizenship of Singapore by declaration registered by the Government, and shall upon such registration cease to be a citizen of Singapore.
(2) The Government may withhold the registration of a declaration under this Article —
(a) if the declaration is made during any war in which Singapore is engaged; or
(b) if the declaration is made by a person subject to the Enlistment Act (Cap. 93) unless he has —
(i) discharged his liability for full-time service under section 12 of that Act;
(ii) rendered at least 3 years of operationally ready national service under section 13 of that Act in lieu of such full-time service; or
(iii) complied with such conditions as may be determined by the Government.
(3) This Article applies to a woman under the age of 21 years who has been married as it applies to a person of or over that age.
unquote.
So, in allowing our (not-so-)foreign talent pianist to "renounce his citizenship without discharging his liability for full-time service under section 12 of that (Enlistment) Act", something's wrong here. By strict interpretation, all Singaporean males must serve NS, period. There's no escape route.
Hmm.