In my case, though, reasonable mini-goal should be something like 30 min of reading per day, or 15-20 pages which roughly translates into 2 average books per month. Everyone is different, of course, but in the long run modest goals win, while ambitious goals fail.
With this low intensity, I feel like you forget a lot about the meaning of new words that you encounter during reading a book. Let's say, if you look up the meaning of a new word on page 10, however, the word was repeated again on page 40. If you kept reading for a long while, you would reinforce its meaning in a different context. With your approach, you already shut the book by reaching page 20. The next day you already forget the meaning of the word, the probability of it is highly likely. Therefore, you would look the word up again as it is important for deciphering the meaning. You start the whole process again. Time-consuming. It would also disturb the flow of your reading.
But as you said, everyone is different so there is nothing written on stone. Anyone can slow down or pick up their pace based on their choice.