Blue Bobbit > Surface Slap Couerl Eel Snakes > Patience II > Cast > Powerful Hookset Ku'ers... there is not a lot of skill involved in that process. I generally try to prep an HQ Ku'er before The Ruby Dragon window so I get a chance at the start of the window. It reads to me that you got lucky within that one month you spent after Ruby Dragon and I believe I mentioned lucky people in my original post. Yes, I have experience Ku'ers getting away that much. If I had to eyeball-guesstimate, I would say close to 40-50% escape rate. But some windows, I just do not get that many bites at all, even after Surface Slap.
The only additional layer to Stethacanthus is the Fisher's Intuition buff from catching x2 Sculptors, which you go and try to Double Hook with Collect on so that you can gauge if there is adequate time left in the window to try for Stethacanthus or leave the window up until the next window which is often an hour, maybe a day later at most. However, there are clusters of Stethacanthus windows unlike Ruby Dragon. If you use the Carbuncle Plushy Fish Tracker website, you can click on the little calendar next to the fish and see the next ten windows. Steth has ten windows between the time of this post and Sunday at 6:26AM EDT. Ruby Dragon on the other hand has ten windows between the time of this post and September 10th. That is a span of 35 days. Again, I would be okay with the distant windows if there was significantly less Ku'ers escaping and a high Ruby Dragon bite rate or vice versa, but the problem is the combination of the extremely sporadic windows and the bite/escape rates.
I extremely disagree that all the windows have been "ridiculous distant." There is maybe a handful of Big Fish that fit that criteria such as Bobgoblin Bass, Suiten Ippeki, Duskfish. Also, if no one expresses they are unhappy with something, the developers will think it is fine. At the end of the day, the FFXIV Dev Team has shown great interest into what the playerbase thinks about the game and they try to adjust newer content accordingly.