Unfortunately I do not have the before/after photos for comparison, but below is a page that I’ve mucked up but managed to fix through sheer perseverance.
You may need to enlarge the above picture (click on it) to see what I’m talking about, but there are two rectangles on the page, one on the top left hand corner of the page and one on the bottom right. Those are the remains of ticket stubs (I can’t even remember for what) that I stuck on the page. I found out, first hand, the reason you do not use double-sided tape to stick things you are later going to paint over; they bubble.
Not only did it bubble, but they stuck to the other side of the page and peeled off. I suddenly had two gaping white holes in my page.
My solution? Brayer over it (this was during the time when I brayered over everything. However I was careful to leave details in the background (ie. the wings) to show through.
The black-over-white text helped complete the grunge-up look.