maybe one could make a blu ray with both options…
Unless TN1 has some great insider secrets, not a single person on this forum (or indeed, apparently, the internet) has gotten homebrew blu-ray seamless branching to work, despite many efforts. If you want to read about it I can try to find the threads and PM you, since it will take us far off topic here for the sake of discussing (so far) completely fruitless efforts.
But yes, it would be fantastic if it would work.