If molecular gastronomy is an evolution, it seems to be too often, as it's popularized, an evolution that evolved right past the point of it all, on to gee whiz, watch what happens and look at this expensive piece of gear.
But at it's legitimate core, it's really just opening up cooking to different techniques that are conceived after the physical basis of food preparation is better understood. If you're ordering exotic ingredients and following instructions, without studying and understanding the chemistry and physics, you're not doing molecular gastronomy, any more than the junior high science "experiment" is really an experiment or even the student's knowledgeable application of science. Doing chemistry exercises by rote isn't "doing" chemistry, any more than the worker who pours the specified amount of maltodextrin or xanthan gum into the factory pot is doing molecular gastronomy. For a great deal of what's featured in the craze, it wouldn't be though of as anything special, if the ingredients had been on the grocery shelves and in use all along. A great deal, if not most of it, has been routine industrial cooking for a very long time.
The point is that ALL cooking is molecular gastronomy, and most of the amateurs who are chasing off to the books and web sites don't yet understand the physical and chemical basis of their regular everyday cooking. Real molecular gastronomy is simply and literally cooking while knowing what you're doing. Most folks would do better to begin by just learning something as basic as the nature of heat transfer.
Heat Transfer and Cooking - Kitchen Notes - Cooking For Engineers
And reading Harold McGee:
Amazon.com: On Food and Cooking: The Science and Lore of the Kitchen (9780684800011): Harold McGee: Books