When working with a multi-page single-sided document, vertical scrolling works fine. However, horizontal scrolling (accidental or otherwise) is hit or miss at magnifications greater than 20%. At 20% magnification, the edges of the work area are aligned with the edges of the viewable area, meaning one can't scroll horizontally enough to hide the live work area. As one increases maginifaction, it becomes possible to hide more and more of the work area while showing mostly empty pasteboard. While this may be useful for people who "store" elements on pasteboard, I find myself spending a lot of time centering the work area after vertical scrolling unless I am extremely careful to only use a perfectly up-down motion when scrolling on a trackpad or similar device. Ultimately, it seems Publisher is too sensitive to side-to-side motion during vertical scrolls, or the (non-adjustable?) pasteboard margins are too wide.
