One of the chief practical benefits for practicing a single kata is that it limits the number of "techniques" that you practice. This might seem like a bad thing, but if you lean more toward the pragmatic side of things this is actually very good. You want to ingrain movements really hard into your nervous system. The more you do a movement the stronger those neural pathways become, the more muscles can be recruited for a movement and the more efficient it becomes. Practicing a single kata checks this box for me.
With only a single kata, each practice session adds to this. Each repetition is another brick added to your defensive wall if you will. Practicing multiple kata can have a dilutive effect. You're not just building one wall you're building a bunch of smaller walls. Each time you practice one you're taking time away from another. It becomes a compromise in training and things need to be balanced out eventually. The single kata takes care of this by shifting your focus on one instead of many. You don't need to worry about training kata that may be acting at cross purposes.
With only a single kata, each practice session adds to this. Each repetition is another brick added to your defensive wall if you will. Practicing multiple kata can have a dilutive effect. You're not just building one wall you're building a bunch of smaller walls. Each time you practice one you're taking time away from another. It becomes a compromise in training and things need to be balanced out eventually. The single kata takes care of this by shifting your focus on one instead of many. You don't need to worry about training kata that may be acting at cross purposes.
