Normally I would do a textbook in the 5 day test anyway. There is nothing wrong with activating the book using the 5 day test method in fact it is preferable. However you will need to give most textbooks more than the mere 5 days consider making it a 15 or 20 day test on a text book or do 2 20 to 30 minute blocks for 10 days. It's fairly common for people to sit 2 or 3 hours with one book for a number of days with the traditional reading method so one hour is quite a saving.
Alex