Ehh Radovid is just jealous of the mages and their power lol, but in regards to your question save Triss for me was the priority (ok i am biased but still), after all Geralt cares about the people close to him and that would imo take precedent over tracking Letho.
-Triss gets kidnapped, Geralt tries to track her down
- Chooses either Iorveths or Roches path, with the Iorveth path having more emphasis on finding Triss
- Her getting kidnapped spans about half the game (side story/main story regardless.......whether it was Geralts priority or not is based on opinion, for me it was)
- Goes ape shit crazy on the Nilfgaardians for what they did to her
- Lovers get reunited....yahh!!!
Plus finding her felt so god damn satisfying.
-I think player with no elven bath scene will go with purse Letho canon, they don't have enough information to save Triss
-But after elven bath scene where Geralt decide to drop everything and go with Triss to find Yen (if you choose it), that is why Geralt need to save Triss from those filthy Nilfgaard
And Geralt don't care about polictic, so friend is the most important with him. Why he care about some witcher go around killing king while his friend in danger
Hmm, maybe I should replay it after my first playthrough with the Iorveth path to see how it goes
For me Roche path is lore friendly, while Ioverth path is more fun.