Why did Cicero switch from "abs te" to "a te" in his later works?

Question

Lewis and Short, in their entry on ab, describe a shift in use of abs in Cicero's works that had far-reaching ramifications:

The use of abs was confined almost exclusively to the combination abs te during the whole ante-classic period, and with Cicero till about the year 700 A. U. C. (=B. C. 54). After that time Cicero evidently hesitates between abs te and a te, but during the last five or six years of his life a te became predominant in all his writings, even in his letters; consequently abs te appears but rarely in later authors.

Do we have any indication as to why Cicero's preference changed over the course of his life? Did he or his contemporaries suggest that abs te had come to represent poor style? Do any subsequent grammarians, particularly those of the Late Latin era or before, suggest any explanations for Cicero's shift?

Answer 1

It seems to be a case of simple regularization. As L&S point out, abs is rarely used before a word other than te; a Packard search yields only ten such cases vs. 277 of abs te (and two of the ten are tuo, tua). This is the kind of situation in which regularization tends to happen: the special rule "use the variant form abs instead of a if the following word is te" seems to have been eliminated by extending the use of the regular form a.

If L&S are correct about the change in Cicero's patterns of usage, that may simply give us a date for when the regularization was occurring. It doesn't necessarily imply either that Cicero himself initiated the change, or that later writers adopted it by imitating his late usage (which seems unlikely anyway -- Cicero was certainly a model for imitation, but did writers imitate one period of his style rather than another?).

(To put some numbers on L&S's "but rarely in later authors": the same search finds 25 post-Ciceronian instances of abs te, vs. about 350 for a te.)