Somehow I get the feeling that "High Fidelity Visualization" is a marketroid's euphemism for "pre-rendered movie that we pretend is our game in progress on the tradeshow floor".
"High Fidelity Visualization" is an interesting term they've tried to coin, but I've had enough experience to know that just because you come into a meeting with a mock or prototype, doesn't necessarily make it a "nuclear" weapon that lets you build automatic consensus. When I'm presenting to a room filled with talented people, I would hope they would be smart enough to see through such a gimmick.
Look at the new Myspace product demo or the reason why Kickstarter stopped allowing these types of conceptuals on certain product types. How do we know that's really the experience we can expect? You can fake anything in design, and that might win you the bid, but what are you going to do when you can't build it and your shareholders are breathing down your throat? You also can't expect people to understand good design when they see it. Some of the most well-produced project prototypes I've seen have been trashed because someone above the designer decided an alternative direction was better based on subjectivity alone. It isn't guaranteed and it often isn't worth the heartbreak.