Interesting, and I could see that working well for some places.
I do something related to this in the interview. Part of the interview is more like things you'd tell a colleague who was considering that: pretty accurate characterization of what you know of the work, your idea of pros, things that might or might not be cons for the person, etc.
Basically, they show up the first day, and their interactions with me are just the same (plus a little extra excitement on my part that they joined, and now able to share proprietary details but without unpleasant surprises). Six months later, and I'm still just the same (plus extra familiarity and increased mutual trust). And hopefully they also are what they seemed to be in the interview.
Though you can't necessarily be 100% candid about everything in an interview, like if you were doing an internal assessment a technology, product, vendor, or competitor. For example, there are personnel issues, company image, proprietary tech, etc. Also, you don't want to say something that ends up misleadingly quoted out of context on a jobs forum or word-of-mouth by someone with a different sense of professionalism or confidentiality, and you don't want to give ammo to a spy from a competitor.
In practice, the line of what to say seems pretty intuitive to hit, and I haven't knowingly had a problem with it. Though, when working at one company doing exotic-sounding, high-value-sounding stuff, I did have a couple candidates grill me on the tech and/or on resources. On those I try to respond something like, "Some of that is very proprietary, and unfortunately can't be talked about much right now until someone joins the team. But I can tell you some of the public information from news articles and such is A, B, and C. There's a few marketecture diagrams on our Web site, and links to some published research papers that detail those aspects better than I could."