The visa requirement exemption applies only to holders of biometric passports.
Obligation to hold a visa:
with regard to exercising gainful occupation (even if the occupation does not exceed 8 days within a calendar year)
Exemption to hold a visa with regard to exercising gainful occupation:
Holders of a long term residence permit issued by a Schengen member state or a valid type D visa, provided they also hold a recognized travel document.
Holders of a diplomatic passport are exempt from visa requirements if they wish to enter into Switzerland: on an official mission or for other travel purposes without exercising a gainful occupation.