Choice inflection points in gamebooks/interactive fiction/CYOA come in many varieties. There a few standard storyline options in "finite-state" interactive fiction, where you don't keep track of changing statistics, or otherwise do anything other than make choices. Branches and bottlenecks are fundamental to choice paths in these things. Note that spin-off interactive fictions are sometimes belabored with extraneous factors that influence the work's structure. Aspects of making interactive fiction have appeared on the site before (green, greener; blue; bluer).

Moondrop Isle – a big text adventure you can play in your browse, written by a crew of nine authors. Features: Urban exploration! - Environmental storytelling! - Puzzles! - Secrets! - Feral guinea pigs!

Click on the dock by the shore to start. It's pretty new so you will find some some unpolished or even buggy things if you spend much time with it, but it's fun to explore. Your progress in the game will be saved in your browser but you can also type

>save

to download an interesting form of save file. If you've never played this type of game before, A Beginner's Guide to Interactive Fiction has some tips for you.