syme and sallust, and demolishing the 'first catilinarian conspiracy'

"the evidence is so inconclusive, and the story, as told, contains so many contradictions and improbabilities, that I prefer to pass it over as wholly or almost wholly apocryphal" (James Leigh Strachan-Davidson)

I'm now at Sallust (Sather Classical Lectures) by Sir Ronald Syme (2002 reprint).  There is a preview in Google Books, and while there is not much text available of the book, the Foreword to the 2002 edition by Ronald Mellor, Life and Scholarship, is worth reading.  It's a biography of Syme, and discusses his life and entire work.

As to Syme on Sallust, Mellor writes:

[...]  Sallust is not Tacitus, but Syme is as loyal to him as if he were as great as his imperial successor. He aggressively defends Sallust against charges of avarice, corruption, and hypocrisy.  Even when Sallust's account is wrong, Syme's explanation excuses him from malicious misrepresentation.  Such is the case of the "First Catilinarian Conspiracy";  Syme demolishes Sallust's version and shows that the conspiracy was spurious.  Although Sallust "comes out of this sorry affair not at all well" (101) as a historian, Syme demonstrates that his problem is credulity—being taken in by Cicero—rather than mendacity.  In any event, after Syme's demolition, no historian can now resurrect that bogus conspiracy.  (emphasis mine)

The "demolition" takes up 16 pages in the book in the chapter "The Credulity of Sallust."  He starts our by saying,

That "conspiracy" is a peculiar fabrication, with variant versions and interchangeable names. It will be expedient to disentangle the original facts (they are few) and briefly trace the proliferations of rumour, allegation, and fable that confronted Sallust.

This he does, but as the story has so many twists and turn, it's beyond my capacity to summarize.  He concludes

If harsh words are in place, it is a little late in the day to condemn Sallust.  Equity will not omit those scholars who, even if they reject the complicity of Caesar, have none the less accepted allegations about other characters, selecting or combining according to their fancy.⁸⁶  The whole edifice is ramshackle. It ought to have been demolished long ago.⁸⁷

The related footnotes:

⁸⁶ H. Frisch, Class, et Med. IX (1947), 21 ff.  He chronicles, beginning with Mommsen, the names of C. John, Meyer, Rosenberg, Gelzer, and Carcopino.  Add that Rice Holmes admits Catilina and even allows Crassus, and probably Caesar, to give countenance to the intended coup d'état (The Roman Republic I [1923], 235, cf. 449).  Note that Gelzer, while toning down his earlier account (Caesar³ [1941], 49) and now exculpating Caesar, none the less accepts a conspiracy of Sulla, Autronius, and Catilina (ed. 6, 34). A. La Penna, however, assumes that Caesar was probably in it: one of his reasons is the fact that P. Sulla was (later) a partisan of Caesar (Stud.it.fil.class. XXXI [1959], 35).

⁸⁷ The procedure of J.L. Strachan-Davidson was exemplary (and rarely imitated) – "the evidence is so inconclusive, and the story, as told, contains so many contradictions and improbabilities, that I prefer to pass it over as wholly or almost wholly apocryphal" (Cicero and the Fall of the Roman Republic [1894], 91). For a brief essay at demolition, see JRS XXXIV (1944), 96 f., in review of Gelzer, Caesar³ (1941); for the full exposure, H. Frisch, o.c. 1o ff.

Cicero and the fall of the Roman republic
By James Leigh Strachan-Davidson 1894, illutrated
(Google Book)
At the Internet Archive / Flip Book (beta)

From footnote 87, for those readers with JSTOR access:  Syme is making many of the same arguments as in his Sallust, including the "ramshackle edifice" (go to page 96):
Review: [untitled]
Author(s): Ronald Syme
Reviewed work(s): Caesar der Politiker und Staatsman by M. Gelzer
Source: The Journal of Roman Studies, Vol. 34, Parts 1 and 2 (1944), pp. 92-103
Published by: Society for the Promotion of Roman Studies
Stable URL: http://www.jstor.org/stable/296786