Christopher Trinacty gives a balanced and helpful account of Vol. I of Giancarlo Giardina’s new edition of Seneca’s tragedies, which he describes as “bursting with emendations” (over 700 of them by my count!). Of 10 conjectures explained by Giardina in his Introduzione, Trinacty identifies two as persuasive: one of these is Phaedra 1275 aspersam for acerbam, which in Trinacty’s view “helps the poetic quality of the description.” But this conjecture must, alas, be discarded as unmetrical, since it generates a spondaic second foot. Other unmetrical conjectures in the new edition include Herc. 698 fruge (which generates an iambic fifth foot), 701 ieiuni (another spondaic second foot), Phoen. 253 cecinit, Pha. 330 acer. Giardina’s 1966 edition of the tragedies, though serviceable in its day, as Trinacty acknowledges, similarly suffered from metrical weaknesses, detailed by Courtney in the CR review which Trinacty cites.
Trinacty correctly remarks that Giardina does not justify the great majority of his conjectures in this edition, beyond citing parallel passages in his app. crit. It is worth adding, however, that Giardina has explained a number of his conjectures in a series of notes and reviews going back to the 1980s, most notably at Mouseion 5 (2005) 159-75. So it is not invariably the case that we are left “puzzling out the justification for such readings.”