"... Most of the time you can find a good move - if not the best move - with a low level of calculation. How low? Two and a half moves into the future. ..." - GM Andrew Soltis (2010)
I guess an example would be the position after 1 d4 Nf6 2 Nd2 e5 3 dxe5 Ng4 4 h3, when Black perceives that 4...Ne3 can be played because of 5 fxe3 Qh4+ 6 g3 Qxg3#.
How do you read chess books?
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Here are my suggestions.
It is very easy to lose focus and get distracted while reading chess books (at least for me it is). Part of the brain is concentrating on reading the notation, which distracts from the part of the brain that analyzes and calculates. To deal with this problem, I found helpful to:
1) Locate the game online. Boom--all the moves are there--now you can shut off the part of the brain that needs to read the notation and move the pieces. That being said, it is important to keep the analysis part of the brain still active, so that you don't conveniently run through all the moves but fail to absorb the purpose of each move.
2) Use a digital analysis board. With this you can go back to the original position if there are variations, etc. It also forces you to make the moves (but thus reintroduces the need to "read the annotation"). One thing that is annoying is to set up a board position, compared to a real board.
3) Use a real board. Some say this is best because it helps you "remember better" as you have to mechanically move the piece, and you're not relying on the convenience of the computer (which we do for so much nowadays). If you are experienced enough you can go through the variations in your head (which is a good exercise). If you do go through the variations over the board, I find it useful to put aside the captured pieces in a group so you know which pieces were involved with the original position. If you need help, try to go backwards, with the help of the notation as a hint. As you get "more in shape" you'll get better and be able to go back further along longer lines, or you'll be able to even just go back to the original position.
Each method above has its merits and pros/cons. This being said I'm a big of fan of #1 since it GREATLY helps me fly through the book. Slowness leads to loss of interest and procrastination. This is a remedy to that. It's also especially very useful, e.g., going through books in descriptive notation (P-K4, KT-B3) which is less common. On that note, knowing the board itself becomes increasingly important in chess, and being able to even just merely quickly name the square is very very helpful. I strongly suggest to everyone to utilize the chess.com vision section (under the learn tab) if they haven't yet. It will sharpen your algebraic reading skills and understanding of the board. Also, allocate time to study and don't just play speed all day!!!! 
In the end, find what feels best for you! But keep going!!! It will pay off!! Now back to reading!
Someone at your level (solid player), needs to do MANY tactics to improve. Do a minimum 10 tactics a day and play LONG time control games.
But to answer your question, chess books CAN be confusing. They require considerable focus and dedication.
Wish you the best, cheers friend.