A whole nother issue

A few days ago, I promised to get back to fixing up Richard Firsten's problematic answers to grammar questions. Although, I said I'd look at backshift, this morning, I was more in the mind to address his second letter, which poses the perennial question: why do we say a whole nother? Richard's reply:

"because it either sounds cute or humorous. And what's really interesting is that you can now find nother in some dictionaries!"

Both of these strike me as true. But one word stuck in my craw: now. A careful reader would be left with the impression that nother is a recent form, perhaps coming out of the seventies when Luke Skywalker famously whined at his uncle, "but that's a whole nother year..." You certainly wouldn't get the impression that it has been in use fairly consistently since at least the 14th century:

• "c1330 Otuel 83 Ich am comen her..To speke wi charles..& wi a knit at heet Roulond & a noer hatte oliuer."
• "c1390 MS Vernon Homilies in Archiv f. das Studium der Neueren Sprachen (1877) 57 280 He wolde him say his onswere on a noer day. "
• "1559 J. AYLMER Harborowe sig. E4, Of Paul I shal speak of at a nother time."
• "1850 ‘M. TENSAS’ Odd Leaves from Louisiana Swamp Doctor 152 Lizey Johnson's middle darter, Prinsanna,..left her husband in the state of Georgy, and kum to Luzaanny an' got marred to a nother man."
• "1963 Word Study Feb. 7, I have to grade a whole nother set of themes."

So why do we have both other and nother? The OED explains:

"From the beginning of the Middle English period, the coexistence of two forms of the indefinite article (an before vowels and a before consonants) often led to metanalysis (the same phenomenon occurs in other languages where the indefinite article ends in -n, e.g. French, Italian, etc.). Variants arising by metanalysis sometimes alliterate with words with initial n- in alliterative verse, and in some cases have become established as the regular modern forms (so that e.g. Middle English a nadder became an adder; compare also apron, auger, etc.), while conversely some vowel-initial forms have gained n- (so that e.g. Middle English an ewt became a newt; compare also nickname). The following examples show the latter process in cases where the variants arising by metanalysis did not become established as the regular modern form."