::The comments below explore various aspects of the same question:  If no reliable published source (as yet) affirms "a marginal Italian victory," how does that claim meet Wikipedia's threshold for inclusion (see Wikipedia:  Verifiability)? 
 ::* How can the reliability of four published sources be "put in doubt" without evidence?  How would "updated" sources "distance themselves from war propaganda"? 
 ::* In the article and on this talk page, the convoy battle of MW10 (3/21 - 3/26/1942) is conflated with the Second Battle of Sirte (3/22/1942).  References that would corroborate that unity are "[p]ractically all the books previously cited" (item 2, 04 May 2007) and "all the reliable sources cited here" (second bullet, 22 June 2007).  Why not more specific citations?  By contrast, that the convoy battle and the Second Battle of Sirte are separate events is supported by specific citations from eight reliable published sources (item 2, 17 June 2007).  With this 0-8 record, how does combining the convoy battle and the Second Battle of Sirte meet Wikipedia's threshold for inclusion? 
 ::* The claim that the Second Battle of Sirte "was a marginal Italian victory" seems to be not a "synthesis of facts or sources," but rather an "analysis . . . of established facts, ideas, opinions, or arguments in a way that builds toward a particular case favored by an editor, without attributing that analysis . . . to a reputable source" (see Wikipedia:  No original research).  Further, Bragadin and Woodman seem to use "fatal" in a limited sense:  Bragadin to refer to the March 23 Axis air attacks that sank Clan Campbell and contributed to the sinking of Southwold (166) and Woodman to refer to just the latter (308).  More to the point, though, which reliable published sources credit the Italian fleet's intervention with having had any but the most indirect effect on the fate of the remaining three ships of the convoy?  Also, how is it "just a 'research'" if no primary or secondary sources state the Italians won a marginal victory?  On a related topic, the U-Boat analogy seems strained since the circumstances bear little resemblance to those at issue here.  Moreover, the analogy seems to assume (without proof) that "some other sources" are biased in favor of the "allies point of view," and therefore editors should not be compelled "to cite only the allies version of the facts."  But, how is this position consistent with verifiability?  On another tack, if reliable published sources expressed no opinion about who won the Second Battle of Sirte or if sources were divided about who won, the article could simply reflect that non-opinion or divided opinion.  However, in this case, six reliable published sources state the British won, while none (as yet) affirms "a marginal Italian victory." 
 ::* The full Macintyre quote also includes this:  "Vian had gained a tactical and moral triumph."  In this context, how is Iachino's partial achievement the equivalent of a "marginal victory"?