The indefatigable Bryan Henderson, an assiduous editor of Wikipedia entries, has made something approaching 47,000 corrections to fix the error comprised of.
Mr. Henderson should be a hero to copy editors and sufferers from obsessive-compulsive disorder everywhere, except that there is good reason to question whether comprised of is an error at all.
Oh, I know that the Associated Press Stylebook says to use comprise only in the active voice, meaning "to contain." And I know that Garner's Modern American Usage is emphatic: "The phrase is comprised of is increasingly common but has always been considered poor usage."
There you are. Rules are rules, though error abounds. Forge on, Bryan Henderson.
But then, if you should happen to look at Merriam-Webster's Dictionary of English Usage, you will discover, in two double-columned pages, that the facts on the ground are somewhat different.
Is comprised of has only been denounced as an error by twentieth-century writers on usage; so if it is indeed an error, it is a recently discovered one. MWDEU also finds that the "compose, constitute" sense in the active voice "is flourishing and can be found in quite a wide range of writing."
I'll skip to the conclusion in MWDEU: "The aspersed active construction of comprise has been in use for nearly two centuries; the passive construction for more than a century. It is a little hard to understand why these constructions that are so obviously established are still the source of so much discontent. …
"Our evidence shows no diminution of vitality in the older senses—"include" and "be made up of." … If the criticism has had any noticeable effect, it may be that it causes some writers to avoid the passive construction, which is slightly less well attested in our files than we might have expected. [Because copy editors have been beavering away at changing it for decades?] The active construction is the harder one to detect and so has not received as much antagonistic notice. Our advice to you is to realize hat the disputed sense is established and standard, but nonetheless liable to criticism."
So what we have with the objection to is comprised of, which appears to be widely understood as written, is something that looks very much like a crotchet.
The sad conclusion must be that Mr. Henderson, along with me and my fellow copy editors, has been expending a prodigious amount of time correcting a minor and inconsequential usage instead of addressing graver issues in text.