It's amazing the way this sort of stuff spreads and incites folks to get really upset ... and sometimes for no good reason.
I recently was handling and shooting some fresh-from-the-factory TSW pistols which didn't have this feature, so I was curious about this subject when it was brought up in another forum. Was it a used gun? Something that someone had had installed either as an option, or after purchasing the gun?
So, I called S&W this morning and asked about this subject. I figured they might have some insight into it, you know?
I was told that back around '01 or '02, when the new owners took over (Remember SAF-T-HAMMER?), that a small number of guns receved this SAF-T-TRIGGER option. I've since found some online references to some used TSW guns, and a Sigma, which had been fitted with this option.
Anyway, it seems the SAF-T-TRIGGER safety option never really caught on as a factory-installed option, and it's not currently offered as a factory option in new pistols. There are undoubtedly some used pistols out there that have this option from that time, or else had it installed by someone else, since there are many listings for companies that not only sold the device, but installed it, as well. It's even listed as an approved safety device for at least a couple of states that I saw mentioned.
And ... when I asked about the proper functioning and use of this locking device, I was told that it was designed to prevent the trigger from moving rearward. When the lock was properly engaged, the device was raised upward through the trigger guard behind the trigger, and it prevented the trigger from being moved to the rear. Here's a link to an article where the device was installed on a Glock.
http://www.countryhunting.com/story.cfm?story_id=58
The sky is not falling ... and there's no new conspiracy against gun owners, especially by S&W ...
However, considering the current interest in such devices by many politicians and advocacy groups of one sort or another, as well as some of the states ... it's probably not a stretch to think that safety/locking devices of some sort or another are in our future somewhere not too far down the road.
Look at the different safety & locking mechanisms already being offered by some of the major firearms manufacturers, folks. If I had to make a gentleman's wager on it, I'd hazard a guess that these sorts of devices are going to be increasing, not decreasing.
In the meantime, if you don't want to buy a S&W pistol equipped with this device, then you probably don't want to buy one of the small number of earlier ones equipped with it ...