On the whole, it was the delivery rather than the content that made it so difficult to read. It’s a personal preference, but I really enjoy when themes emerge out of the plot, rather than when they are stated so explicitly. It’s more difficult to do it this way, of course, but Heinlein showed he was capable of it in the first half of the book, which is part of what made it so frustrating to read the last half.

Also, it bothered me that the only avenue to enrichment for these people was through sexual liberation. Even the movie Pleasantville had a character that found joy in life through reading instead of sex. What made this even worse was Jubal, the most non-sexualized of the characters, went down this avenue. Wouldn’t it have fit his character better to find enlightenment through his intellectualism, or logical reasoning? If it’s to be found that way, he would be the one to since he “groks” without speaking Martian.

As I think about it more, it’s not that Heinlein necessarily had to show that there is more than one path, but I think it would have fit Jubal’s character better. Of course, that may have gone against Heinlein’s overall argument that the male-femaleness of humanity is their greatest gift.

My initial theory is a split between two elements, which likely boils down to one element: (a) phase of life during reading the book and (b) taste for Heinlein’s particular style.

Heinlein’s ideas on sexual liberation permeate all of his literature (that I’ve ingested so far), on top of recurring characters in a consistent universe. Rather than seeing them as actual fantasies (although his spread of women :-P would certainly qualify), I’ve taken them as a fascinating extrapolation of what the “free love” concept could bring to the table.

The more general reaction is an honest pleasure in simply reading the various conversations and dictations offered by the characters. Even when Heinlein resorts to his soapbox, I enjoy listening to his description of the view from up there.

I wonder if those who appreciate this book more deeply are those for whom many of Heinlein’s ideas bring a new perspective to their table. Perhaps you had already tasted many of same concepts, thus rendering the feast to be instead a refrigerator of leftovers.