Neither, that is just straight fact. And if it was thought otherwise, the company deserves your money.
It's the same principle as if it were anything else. You might see it as "WE at (insert ANY manufacturer) would like to encourage the enduser to NOT use the specific tool engineered for a specific job that is in the user manual as it may cause an accelerated wear on the product otherwise not occuring with normal repeated use."
It happens in every field. And the people who know about it the most, are usually the mechanics/armorers/self-fixers.
Will you ever get a manufacturere to admit a mistake? Not without a court action. It's bad for business and why would you want to say you made a mistake? It would be better for them to advise the user to use a method not in the manual. Fortunately for S&W, they would advise using a pen cap or similar item, somewhere in a press release or in an updated manual, when disengaging the sear disconnect lever.
But I digress. Kudos to S&W for getting the contract. They are itching to get back in the LEO market big time.
I'm not really a huge fan of the M&P and IMHO you are making a mountain out of a molehill. Outside of an "exigent" circumstance, no sane person would use the backstrap pin thing to push the takedown lever, as it's too much of a pain in the ass to remove it from the gun constantly, anyways. You could use a cleaning brush, a plastic cleaning rod, or any of the myriad of objects likely to be on someone's gun bench while they're cleaning the gun. Hell, the swiss army knife that's always in my pocket would probably have something on it that could be used to press the pin.
If I owned an M&P I'd find a way to remove the whole damned thing or just get it so I could take the slide off without using the stupid lever.
BTW, in terms of "having defects and never admitting mistakes" Glock is pretty much the crowned KING of that, and I own more Glocks than everything else combined. For example the Gen4 G19s and G17s that came out originally were completely
****ed up, but Glock would never admit they
****ed up. I will say though that I got my "early" Gen4 G17 back from them in 2 weeks and it's basically perfect now. (It was having massive ejection problems). Even the trigger feels better too,f or some reason. (Another defect with some of the Gen4 guns floating around out there that they won't acknowledge). In the end though I don't really care what kind of smoke Glock wants to blow, as long as I get a good pistol out of the deal, and all of mine have been excellent. This is literally the first gun I've had to send to them in the past 4 years. )
While I'm at it, Beretta, Sig (Any mosquito owner knows what I'm talking about... talk about a train of lies) HK, and probably numerous others, are all guilty of the same brand of "offenses"... so the type of stuff you're talking about, is pretty much par for the course for a number of manufacturers.
-Mike