The scroll wheel on the mouse can be useful to speeding up workflow in Premiere Pro, that is, if you know how to use it. This is especially true if you are switching to Premiere Pro from another application. For example, Final Cut Pro editors are used to using the scroll wheel to move the timeline vertically to see more tracks. In Premiere Pro, the scroll wheel moves the timeline horizontally. This may seem disorienting at first, but you should know that you can use the mouse to scroll vertically. To do this, hover the pointer over the scroll bars in the timeline, then use the scroll wheel on the mouse to move the timeline vertically.
The scroll wheel has an additional function, and that is zooming in and out of the timeline. Sure you can type the = and – keys to zoom into and out of the timeline, but if you hold down ALT (Windows) or Option (Mac OS), and scroll with your mouse you can zoom in and out that way. Scrolling down with the modifier key enabled zooms out of the timeline while scrolling up zooms in.
Just a couple of tips for your scroll wheel that should save you time as you manipulate the timeline in Premiere Pro.