How can it be bad, if done moderately and linked to relevant pages? Sometimes you need to use your brain, instead of reading random bollocks that people post.
Your target keyword is "red shirts", so naturally you wrote an article about red shirts in the past.
Now you've just written a new article about blue shirts, but you also included a link to the article about red shirts using the anchor text "red shirts", telling people to check out that article.
What kind of an idiot can say that's bad? It's what all "normal" websites do, when they don't even know what's SEO...