The example you link is interesting:
In a letter to Michelangelo on 6 September 1533, Cavalieri reports that Cardinal Ippolito de’ Medici wished to commission rock-crystal intaglios of Michelangelo’s Tityus and Ganymede from the gem engraver Giovanni Bernardi; he apologised that he had not been able to save the Tityus:
Il Cardinal de’ Medici à voluto veder tutti li vostri disegni. E sonnogli tanto piaciuti che voleva far fare quel Titio e’l Ganimede in cristallo; e non ò saputo far sì bel verso che non habbia fatto far quel Titio, e ora il fa il maestro Giovanni. Assai ò fatto a salvare il Ganimede.
[Cardinal de’ Medici wished to see all your drawings, and they pleased him so much that he wanted to have that Tityus and the Ganymede made in crystal; I couldn’t see how to prevent him from having the Tityus made, and master Giovanni is doing it now, I worked very hard to save the Ganymede].
I find I’m pretty happy to let it through there. The register is non-informal-to-formal. But it’s also a register and scholarly context where a certain elision of anything strictly unnecessary is good style, and when I read it I can’t help adding in the back of my mind a suppressed “for the fact”: “He apologized for the fact that he had not, etc.”