As far as I’m concerned, the amount of flexiblity you need is the amount that is required to compete in your sport, without the inflexibility of your limbs hindering you. Hyperflexibility has not been shown to be beneficial unless you are a contortionist.
Stretch to reach the flexibility level you need.
Stretch to help recover from your workouts.
Stretch to maintain the level of flexibility you need.
Flexibility is only one part of the equation that allows you to remain injury free. Restoration methods, proper strength training and sport technique, and proper nutrition are all equally valuable.
You reach a point of diminishing returns on your time. Would it be better to spend 3 hours a day stretching, or would it be better to spend that time in relaxing, recovering, or training?
Yer call amigo
Shaf