Nice observations Cam!! I think your point about large bass caring more about being near a significant food source is more important that the proximity to deeper water.
I had an interesting converstion with a friend last year about figuring out where to go for dinner. The conversation quickly turned to fishing. The question that arose was "If you were going out to dinner, would you go where a skinny man told you to go, or where a fat man told you to go?" Obviously the fat man has more experience in dining and would then know where the best food could be found.(Just an observation, not a slam against large people) While relating that in fishing to the various sizes of schooling tuna, we concluded that fish who want to be successful feeders should try to follow and hang out with the bigger fish who know where feeding is best. Big fish spots can be good for generations of fish.
Another interesting comparison I like to make is to the nature program that shows large crocodiles slamming wildebeasts as they cross a river. The migrating wildebeasts only cross this river once a year, but every year there are huge crocs there ready to ambush them. I can only assume that these crocodiles have learned from years of experience to be at the same spot at the same time each year. This is a one-time feeding opportunity that will help them to sustain themselves through the rest of the year. Bass must have the same experiences whether it's a crayfish hatch, trout plant, or whatever. The experienced fish know where to be in order to get fed.
The "book" that speaks in length about bass wanting to be in close proximity to deeper water is based on a few key assumptions. That these bass live on a body of water that fluctuates dramatically, that the bass' food source is also effected by the water dropping, and that bass are the apex predator of that body of water. The rules would then change if all of these conditions are not the case. If a body of water does not have key structure leading the the bottom of the lake, if the water does not fluctuate dramatically, or if the primary food source strictly relates to shoreline cover you must take that into consideration. In many of our lakes where stripers are the apex predator, bass will position themselves differently. For example, if stripers are pounding trout after a plant, many of these trout will seek shallow cover to offer shelter. Bass who know what is going on will be positioned shallow to pick off these vulnerable trout, letting the stripers do the work of positioning their food for them. A successful bass will then remember his feeding opportunities and do the same program until that strategy is unsuccessful. Even lakes without striper will have the same scenario as big bass lie in wait and let medium size bass push food to them.
The bottom line is that to understand big bass, you must first understand the feeding conditions needed to grow that bass. If there are more opportunities to feed shallow or deep. When water fluctuation or temperature will significantly reposition a bass' food source. What seasonal opportunities are present, and where will bass make the most of those opportunities. Whenever you catch a big bass, make specific notes on location, conditions and season. Chances are if one large bass felt the need to be in a location, another will find the same location beneficial in the future.