It's a tricky one. On one hand, a toolbar reduces clutter in the tab order, which can make things more efficient. On the other hand, it has the range problem you describe, plus it makes it harder to have keyboard shortcuts which don't require you to focus the specific control. For example, in Firefox, when you're focused on the play/pause button, you can use left/right/home/end to seek, up/down to adjust volume, all without having to find the specific control. But you can still tab to the control if you wish, which is great if you don't know about the shortcuts.