Question: Would anyone, who gives up on logic and sensibleness to share and to find insight to live a happier and better life, lose their ability to coherently speak, understand and categorize their life’s experiences?
Answer: I think so. I think the key word in your question is “share”, after all “speech” is only there for communication.
And here I think we find the necessity to place an “intention” over logic, sensibleness, over finding insight into living a better, happier life. As long as we want to do that only for ourselves we do not need the ability to speak coherently. We only need the eloquent ability to express ourselves if we want to pass our experiences onto others.
And that opens up an even deeper layer. Nature, our own Human “structure” is built in such a way, that revealing, understanding true, meaningful and happy life is only possible if we do not hold it, gather it for ourselves, but we become a pipeline, passing on everything we revealed to others.
Then we are not limited in tasting, sensing and attaining by our own restricted, egocentric and subjective vessels, perception. By passing everything onto others in a selfless, transparent way, by expressing through speech and writing all the we attained, our receiving, attaining ability becomes limitless, we ourselves “as if “ become the fountain of Wisdom towards others.