ERRATA / ADDITIONS: 7:03 That's a 2 going to 3 of course, my bad! 18:26 could also be regarded as a chromatized (authentic) cadence to B flat, the bass clause still being 'evaporated'.
Thank you for your brilliant explanation, I really enjoyed it and learnt a lot - actually, Scipione Lacorcia wasn't in my horizon before watching your video! 18:50 Since you encourage your audience to mention tritonic relations earlier than (or at least contemporaneous to) the passage in "Ahi, tu piangi", I feel free to note this observation: In Gesualdo's famous "Moro, lasso" there's a quite similar progression illustrating the words "dolorosa sorte": Using modern chord symbols, one could describe the two adjacent chords (with the word "sorte") as Bbmaj7/F - E and - two bars later - Fmaj7/C - B. Again, the skeleton is built by a regular two-part phrygian cadence combined with a chromatic agente. It's just one more example which shows the close relatedness (and nearly literal quotation) between the two composers.
Honestly, I have difficulties enjoying this video, which is a nice creation in all other aspects, due to the fast changes between commentary and music. My main point is, that I cannot *really* listen to the music, because there seems to be always a next comment waiting to interrupt the beautiful sounds and cadences. Also it seems that the music goes on in the background, which I find really sad, because I would much rather prefer to listen to the whole thing. I find there is no breathing between music and the commentary. It leaves a really hectic impression on me. I do not want to belittle your work or anything. Just want to tell you, that sadly my mentioned aspects make it awful to watch this video, frankly.
I appreciate your comment. If you want to listen to the music, you may follow the reference recordings given at the very bottom of the video description. In these kinds of videos, I always try to show what I am talking about while at the same time not exceed the quotation length of music snippets, which is inbetween 5 and 7 seconds. Before this video, nobody seemed to care, but you are not the first one for this specific video to point it out. I will think about how to handle this conflict of interests for future videos.