Able to pass a thorough test on the book is about all comprehension could be. I can pass a test on "Jonathan Livingston Seagull"- who, what, where, why blah blah blah but I don't understand all the deep esoteric meanings in it. I think that takes more INCUBATION- reading a book, going about life for a few years then comming back and saying "OH, now I get that."
If I read a book on landscaping and "know" alot from the book I still can't walk out of my house and do everything I read about (but I'd rather spend 1/2 hour than 5 hours getting to that point)- I still have to have the book with me and try things out and fail alot at it and get better over time.
For now, to me the word comprehension means able to basically understand the important points enough to help me do what I have to do now and have the fine details located for further study.