Although there are probably more such examples in the list of proverbs, what is stated here is true, but it's not an acknowledged proverb. Let's keep the page for now and extend it with diagrams and reasoning, while looking for actual proverbs that relate to it.
What criterion of proverbiality does it fail that it can't be properly called a proverb? Is it not a "pithy saying teaching a guideline of good basic play", as I'd define the term?
A proverb should be known in literature of Go books or professional go commentaries as a proverb, preferbaly by having references of Japanese, Chinese or Korean wordings of the proverb, or English translations, occurring at least once and preferably more often.
Anyone can come up with dictums or proposals for something that sounds like a proverb and this particular one is definitely a good candidate. But the page as it is, is meagre to qualify it as a real proverb.
That's why I suggest to expand upon it, not to delete it.