By cohesive, I mean that the ideas and opinions expressed in the various notes in a garden don't need to agree with one another. It's perfectly fine to have one note expressing the need for gun control, and another claiming that gun control is horrible.
In fact, having disagreeing notes is perhaps more healthy than having complete cohesion.
Considering that a large notebase acts as something like a "second brain", it's important that our brain considers multiple sides of an argument rather than going full-tilt into a belief. When reviewing notes in the future, idealogical dissonance can cause (or force) critical thinking.