This is simply not true.
I don't know what you are doing, but you are most likely doing it wrong.
The walkthrough mode is here to prove you wrong.
No worries.
There are a lot of options, some are significant, and some are not. Some will change things on a large scale, some will only impact the current dialogue. It's easy to get lost. I wanted it that way thinking it would push the player to play and replay the different paths in order to find new elements of the story he could have missed.
However, I also do understand that it might be a source of frustration. Especially when you feel like hitting the same wall multiple times.