Laudator Temporis Acti

John Chadwick (1920-1998), Lexicographica Graeca: Contributions to the lexicography of Ancient Greek (Oxford: Clarendon Press, 1996; rpt. 2003), pp. 24-25 (discussing "the lexicographic equivalent of Occam's razor: sensus non sunt multiplicandi praeter necessitatem"):

But at this point I should like to record an experience that I had more than forty years ago, when I was working on the Oxford Latin Dictionary.

It fell to me to prepare the first draft of the article on ineptus, a fairly straightforward word applied to persons or their actions and roughly corresponding to English foolish. However, there was one passage which did not fit this meaning, the famous poem of Catullus (17) which begins:

O colonia quae cupis ponte ludere longo
et salire paratum habes sed uereris inepta
crura ponticuli axulis stantis in rediuiuis
ne supinus eat ...

The omission of any punctuation is deliberate. Inepta is interpreted by virtually all dictionaries and commentaries as meaning badly fitted together, which is the expected 'etymological' sense; as the Thesaurus Linguae Latinae puts it, 'i.q. male aptus.' But here my principle came into effect; why are there no other examples of this meaning? Could it have any other sense here? The answer is that so long as inepta is associated with crura in the next line, this must be the meaning. However, I observed that there was an idiom in which ineptus was closely associated with a verb and in agreement with its subject, to describe the folly of the action indicated by the verb. A good example, although rather later in date, is from Persius, who states that freedom is not conferred by the wand waved by the lictor in the ceremony of manumission:

hic hic quod quaerimus, hic est,
non in festuca, lictor quam iactat ineptus.
                                                 Pers. 5.175.

This does not mean 'in the wand waved by the fool of a lictor', but 'in the wand which the lictor, fool that he is, waves'. There are other examples of this idiom. Once this is appreciated, we can see that it will fit very neatly in Catullus too; inepta is not accusative plural neuter, but nominative singular feminine agreeing with colonia. Thus it means 'you are afraid, fool that you are, of the supports of the bridge'. I was very pleased with this discovery, and wrote it up in a note which I intended to send for publication to one of the periodicals. But before doing so, I took the precaution of showing it to a few Latinists of my acquaintance, and was shocked to find that they all rejected it out of hand. They had been reading Catullus for years, and they knew that he used the word in this out-of-date sense. I, as a young and unknown lexicographer, could not possibly know better than the distinguished line of commentators who had long ago decided the correct interpretation.

Oxford Latin Dictionary, s.v. ineptus, sense 2:

(app. after the primary meaning of aptus) Not well joined, loose.
o Colonia quae cupis ponte ludere longo..sed uereris ~a crura ponticuli axulis stantis in rediuiuis CATUL. 17.2.

C.J. Fordyce (1901-1974), Catullus: A Commentary (Oxford: Oxford University Press, 1961; rpt. 1990), p. 141 (on 17.2):

inepta: 'ill-fitting', the opposite of aptus in its literal sense of 'well-fitted' (in which it is opposed to solutus, 'loose', in Cic. Orat. 228); the word is not so used elsewhere.