@fstnando77

From Kata description:

Sometimes a line may be valid in one direction but not the other. Such a line is still considered valid.

I agree with amitznati. In the following case (Good5):

   +-------+          
   |      +++---+     
X--+      +-+   X 

You are also not 100% sure which path to take, however return true.

Did you read the hint in the Kata description?

Imagine yourself walking a path where you can only see your very next step. Can you know which step you must take, or not?

If you are not 100% sure which step you must take then line is not valid.

It must be possible to follow the line with no ambiguity

• e.g. When starting from bottom-right X you will get to a junction. Do you turn left or right? You don't know...
• e.g. Similar can happen when starting at the left-side X

Since the line is not "valid" in either direction then it is not considered a valid line.