Yes, I read Jackson in the early 1980s and I'm sure it has influenced my thinking about data design and program design ever since; these messages seem very familiar and intuitive to me so I must have internalised them. They are also one of the reasons I always found SQL frustrating, since it masks the natural hierarchies in the data that can be used as the basis of program logic.

One thing that Jackson misses, though, is that there can be multiple hierarchic views of the data: this doesn't apply to the indexed sequential files he was originally working with, nor (directly) to XML, but it does apply when you extend Jackson to other fields.