Well, that's good. I read the novel Dune one time, and it was pretty interesting, but I've never been able to convince myself to read any of the sequels.
As far as seamless branching goes, the technology of DVD is different enough from LaserDisc that the way DVD does it was never possible on LD. The idea existed, though, and was sometimes put into practice.
For instance, the Criterion Special Edition of Close Encounters of the Third Kind was constructed so that, played straight through, it presented the original (1977)theatrical cut of the movie, but the scenes which were changed or added for the rerelease version were placed at the ends of the sides where they would appear, and the corresponding edit points in the film were bracketed with chapter markers. Since this was a CAV disc, proper use of the chapter-programme function according to the included instructions would play back the 1980 cut with very brief (2-3 second) pauses at the breaks.
There were also some interactive CAV discs, e.g. Murder, Anyone? and Many Roads to Murder, which used the auto-still-frame and frame-search functions to allow the viewer to choose various alternative storylines. More sophisticated than these home versions were the arcade games, Cliff Hanger, Dragon's Lair, Space Ace, and the like, which required an external control computer and used the LD for higher-quality graphics than game machines could produce at the time. There were also industrial and educational players and discs which ran the same way, either from a programme on the disc itself or from an exterior computer. I think windows XP may actually include a driver for the Pioneer LD-V8000, the last and greatest of these machines.