The results of the experiment are reported here. I don't think the findings are gob-smacking. The book is more complex than the film. Both are rather flawed. Seeing the film has the advantage of boosting the visualisation of certain characters, and the disadvantage of imposing the simplistic characterisations of the film onto the text.
I found that reading the book and seeing the film in close succession was a worthwhile experience. Thinking in detail about the contrasts between the two was entertaining. More enriching, in other words, than spoiling. I think avoiding seeing a film of a book one likes (or vice versa) is probably unnecessarily fastidious.
