Should he copy and paste the entire column?
No, he should make an attempt to answer the question that was posed rather than point at a generic answer that resides on another site.
Many of us put in the effort to answer the same questions over and over again. Doing so isn't a waste of time; it's a matter of providing a "personal touch." If we all answered like merlyn, ninety percent of the nodes on this site would consist of one sentence answers: "I answered that here", "I wrote a node on that already", or "I have a column on that." Are those the kind of answers that attracted you to this site?
FWIW, the pink llama was my first book on Perl, so I recognize merlyn's contribution. I'm not under the impression, however, that he has earned the right to be smug and self-serving or that he should be placed on a pedestal. The fact is that there are many "unsung heroes" on this site who not only contribute to the community consistently but whose perl, communication, and interpersonal skills are far better than merlyn's.¹
I'm in total agreement with hattmoward's comments.
1. Personally, I aspire to be like the tillys, tyes, dwss, chromatics, Erudils, jmcnamaras, demerphqs, jeffas, (and so on) of the world and think of merlyn as an anti-idol of sorts. I wouldn't want to be like Abigail either, but at least he has a real grasp on the technical issues.
"My two cents aren't worth a dime.";