They can know what they are doing (or know something about a subject), but still not have enough insight to give a meaningful recommendation.
You know that Consumer Reports is not the last word, but what about the rest of CR's considerable subscription base? There is a whole lot more to a speakers objective performance than just a measurement of frequency response.
Speaking of which, what resolution is the measure? Is it only on axis? Is it anechoic or quasi-anechoic?
If Consumer Reports is rating speakers for the public, shouldn't they be doing it by taking advantage of the most current knowledge in the field of psychoacoustic perception, and loudspeaker measurement? Not that they need to expound on how bias will likely cause speaker X to sound "better", or how speaker Y has a highly resonant cabinet.
I'm almost 47 years old and have been into audio since I was in junior high, so I understand fully what you are saying. I wouldn't look to CR to be the ultimate authority on anything, but they are at the very least _one_ good source of information -- even if it is not complete, it is almost always accurate. Their speaker testing could obviously be more complete.
Although I agree that they could do a lot more with their testing, they have limited resources and are writing for the mass market. If they were to attempt to buy and test a variety of speakers (or TVs, or bikes, or cars) from every mfr in the world, they'd be stuck doing that until the end of time. They try to get a representative sample from mfrs and retailers that _most_ people (granted, maybe not many of us here) would buy from, do some basic tests, and get the report out before the mfrs change their model lines. Remember that regardless of what they are reviewing _most_ of their subscribers are probably not way into it. So, not only do they not have the time,money, staff, and/or facilities to do in-depth testing on every product they look at -- most people wouldn't want to wade through all of the nitty-gritty details anyway. They just want to know which battery to buy for their car or whatever, not the details of the electro-chemical reaction and the type of plastic used in the case, etc.
If a person is really into _anything_ -- golf, cooking, cars, hiking, mountain biking, A/V gear, photography, you name it -- they will almost certainly already know most if not all of what CR has to say about the subject and related equipment. That's to be expected. I happen to be into cars and know a little bit about them. I don't get upset when CR prints some basic advice for people just because I'm familiar with it -- I just skip over it. Likewise with their reports about A/V gear. I'm an electronics tech so there's not much I will read in CR about what specs mean or how to hook up gear that I don't already know, but I realize it's useful to the majority of subscribers. Their testing is still very interesting to me because I know it is accurate and I can trust it. It may be somewhat limited in scope and I may wish they were more comprehensive sometimes, but I'd rather have a limited amount of accurate info and test results than none at all.
I continue to subscribe -- both online and the magazine -- because there are a lot of products/services that I _don't_ know very much about and CR continues to be very helpful.
If I could only subscribe to one magazine, it would be CR. They've saved me an incredible amount of time and money over the years. I look at it like this -- it is almost guaranteed that in the course of a year a person will save far more in time and money than the subscription costs. It is very common for the top-rated products to be hundreds of dollars less than lower rated ones. CR also saves people the hassle of buying an inferior product and having to deal with returns, repairs, warranty claims etc. It's so nice to be able to read through a report and in a few minutes to an hour or two know what to buy. It saves hours of phone calls, Internet research, wading through marketing hype, etc. They point out financial traps and rip-offs to watch out for. The list of benefits goes on and on...
Suffice it to say that subscribing to CR is a no-brainer. Those of us who are into audio (or whatever else) can simply ignore what we feel is irrelevant to us.
In this particular case, I think their testing is useful because it allows us to compare their results with the mfrs' and also, while it's true that some people don't like an accurate speaker, I would certainly count accuracy as a positive thing -- all else being equal. It's a good bit of info to have -- one piece of the picture anyway.