Once you know how each type of cadence is constructed, you will be able to apply them in your hymn playing and harmonization exercises. Because cadences are one of the main techniques which helps to create a form in the piece, they can be very handy in improvisation and composition as well as to discover them in real organ pieces.
In fact, I believe that after watching this video, you will want to go ahead and simply find different types of cadences in the pieces you currently play. This process of discovery can be very enjoyable and it can lead to real revelations.
Try to see the music you play with different eyes, like a structure which has many cadences strung together. Then you will begin to feel the same thing like composers did when they created it.