Pathfinder panel vs pathfinder effect.

One of the chapters in the Illustrator Essential magazine- the graphic design magazine that I discovered recently- which was dedicated to Pathfinder gave me a chance to have a closer look to this tool. Thanks to a simple guide I was able to understand  the differences between the Pathfinder panel and the Pathfinder effect.
I started from a simple exercise on how to add some character to a plank of wood. In the Illustrator I drew a pointed rectangle using rectangle tool and modifying it with the direct selection tool.
To add some chips out to the basic shape I used the Subtract option from the Pathfinder effect. With a brush tool and I defined the chunks that I wanted to take out. Next I grouped the object which made it easier to manage shapes.

I went to Effect-Pathfinder-Substract and removed the unwanted parts from the basic shape.

It resulted in a shape which reminded a piece of chipped wood.

To compare the Pathfinder effect with the Pathfinder panel I created a similar shape but this time I used the Pathifinder panel. I drew the pointed rectangular and defined the chunks with a brush as I did in the first instance. I opened the Pathfinder panel (Window- Pathfinder)  and clicked the option "minus front" . 

I edited the two shapes and started experimenting with the selection.I was manipulating the shapes with the direct selection too. My conclusions of this experiment were:

1. With the Pathfinder panel you are not able to edit the original object. The changes can

 be applied to any combination of the objects, groups or layers.

2.In the Pathfinder effect you can still select and edit the original object, you can use the appearance panel to modify or remove object, but the changes can be only applied to groups, layers and text objects

Moreover while edited the pathfinder effect treats brushes as shapes instead of simple paths.