I understand the frustration, but we have to have some trust in what they say (until standard options aren't working - THEN it's time to verify). I mean, do we assume the system specs are all wrong or that the error codes are incorrect or that they ran the BIOS or diagnostic reports on a different computer or, and this is my personal favorite, that they did nothing we already suggested but said it all worked out fine or didn't work at all? And questioning a dozen times isn't going to help if you can't expect accurate feedback (as that will merely continue).
We're going to get burned this way from time-to-time (and it is a PITA), but I agree it should only apply in cases where things don't add up - not become a common practice in every case. Yes, it does happen - but it's not all that frequent. Yes, in this case you were fooled and wasted some time - but you gave the right answer (even if it was for the wrong product) and that ultimately solved the problem (but by the OP figuring out it was the wrong model) and not by your extra efforts to provide the details) - but I'll bet it hasn't happened to you all that often (perhaps more than us as you've more posts - but I'm willing to wager it isn't all that common).
I do agree, however, that if standard procedures aren't working and it's making no sense, it may be time for something like Speccy or screenshots or the like just to make sure. I'd go so far as to say it's a logical next step in such situations regardless of the possibility of incorrect information (as other information may tell the tale and we may find the problem is actually something else).
Re-reading what you said, I believe that's what you meant anyway - but I just wanted to emphasize that there's a time for doing this in specific cases ONLY. Sometimes even the initial post is enough to warrant suspicion and put me in this frame of mind (especially if it varies a great deal from system specs or makes no sense) - then I may even start out that way (at least to a small degree until it is disproven or proven). It's a judgement call we all have to make at some point in the process on specific cases if things aren't adding up.
Thanks for the reminder and the value of your experience.