You wouldn't have wasted time necessarily, but you're correct in saying that the videos do help to retain the information. I remember when I was taking path there were a couple times were I remembered something because of the way he drew something out in a video... and I watched Pathoma on 2x speed without giving it a great deal of focus. It's rare that something is explained so well that it only takes one time for you to understand it... and Pathoma provides that for a decent number of topics if you watch the videos alongside the book.
As far as additional information, there is minimal true note taking needed. Sometimes he elaborates on something or if you want to draw the image he draws out I guess that could help you. I personally don't write a ton, because I like to focus on what's there and my highlighting is focused mostly on the things he specifically says are high yield, which helps when answering questions, because that info is often present in the stem. There might have been one or 2 corrections, the only one I remember him saying was the book saying an intracytoplasmic bridge for something that was supposed to be intercytoplasmic. It will take you more time to watch the videos as well, but I don't think you're really getting the true utility of the program if only reading the book.