Can a Visa Waiver National Apply for a Uniform Schengen Visas (USV)?

I recall seeing Gayot Fow claim that this was possible, which one does not contradict lightly. On the other hand the "conventional wisdom" is that a Schengen consulate would probably refuse to examine a visa application from an Annex II national. And the Schengen rules I can find do not clearly seem to contemplate that possibility.

The rules context is quite different. A third-country national wishing to enter the UK needs to have either an "entry clearance" (applied for in advance) or "leave to enter" (granted by the immigration officer at the border). So having an entry clearance does, in principle, mean that you don't need to convince the IO to take the positive step of issuing a leave-to-enter, just that he should honor the entry clearance you already have.

In contrast the Schengen Borders Code states that all third-country nationals go through the same "thorough check", described in Article 8, subsection 3(a). Verification of a visa for Annex I nationals is in addition to that common procedure. At least as far as the EU legislation goes.

Neither does the Schengen Handbook for the processing of visa applications mention anything (in either direction) about visas for Annex II nationals.

This does not conclusively prove that there can't be an administrative practice of issuing visas to Annex II nationals who bother (and pay) to apply for one. But such a practice could well vary between member states. In particular, if you succeed in applying for a visa from one member state, and then enter the Schengen area through another member state, it might be that the border guards there would be confused rather than reassured if you present a visa.

I have found something in the Schengen Visa Code, that could be interpreted as excluding Annex II nationals from applying for short-stay visas. Article 1 of the code concerns its "objective and scope." Its second section reads in part:

2. The provisions of this Regulation shall apply to any third-country national who must be in possession of a visa when crossing the external borders of the Member States pursuant to Council Regulation (EC) No 539/2001 of 15 March 2001 ...

Countries whose nationals "must be in possession of a visa" are listed in that regulation's Annex I, and those whose nationals are exempt from a visa are listed in Annex II, which is why people are often called Annex I or Annex II nationals. Since the paragraph quoted above explicitly applies the regulation to Annex I nationals only, the regulation simply does not apply to Annex II nationals.

I grant that this is somewhat tenuous, but it does seem to be, at least possibly, a basis in law for a Schengen-wide policy of refraining from granting short-stay visas to those who do not need them.