Paul's answered your question.

I have long kept my QAT under the Ribbon because it is too long to view at the top. This costs some screen space but my QAT extends the width of the page. You may be underutilizing this valuable tool with only the default setting. It lets you easily put the Ribbon commands (as well as many not on the Ribbon) you use the most on all of your screens without jumping from tab to tab.
Modifying the QAT in Microsoft Word