It is a standard functional test of a firearm to (unloaded) cock it, put the safety on, pull on the trigger, let go, take the safety off. The weapon should not fire, that is, the hammer should not drop. If it does, it is defective. Bad trigger or safety, something worn out of spec, not fitted right in the first place, etc. Any weapon can do that. Many do, for the reasons stated. I would hope that a factory built 700 would not. I've had a small ring Mauser do that in the early assembly stage. The parts, from many different guns and 100 years old, didn't all work together without fitting.
People tinkering with all the bits to get a better trigger can seriously screw up anything. Even so-called professional gunsmiths. I would venture to say that the majority of the problems stated are from either worn out actions or someone tinkering, and most likely tinkering because the number of shots to induce that much wear would cost more than any of use could afford in a lifetime of shooting. Is a 700 more susceptible to this than others? I dunno. Maybe. I would also venture to say that given the number of 700's and 700 based rifles out there, there would be a bigger chance of any problem being seen. I mean, it's like saying that SBC's are susceptible to rocker arms grenading on you, here's some stats, a thousand of them blew up last year. Well, given the billion SBC's out there, it's a pretty small problem, and of those thousand, 500 had big cams added.
I also know the military likes 700's because the pre-64 Winchesters were discontinued (in 63) and the post 64's extractors were said to possibly foul after several hundred rounds at a single shooting. You know, like when you're shooting up an entire enemy company by yourself or with just a spotter. The 700, with it's conventional Mauser style large extractor was the only other choice they had at the time, so they went with that. That is from an interview with the father of the modern Marine Corp Sniper program that I read within the past couple years.