You may experience an anomaly in Word 2010 that looks like this:
The expected result is supposed to be normally-displayed text. In the picture below, the text that is circled contains approximately 35 characters when rendered correctly. It is squished together to the point of being illegible in the incorrectly-rendered scenario.
Read the Answer to this question to see why this occurred in my case, and what I did to diagnose and resolve it.