It seems to be an issue with documents I've got from elsewhere, quite possibly from other operating systems. Microsoft is typically cagey about what’s changed in the patch. The update is available from here or AutoUpdate on your Mac should grab and install the patch. Microsoft has released another patch for Office for Mac 2011 called the 14.4.3 update. It doesn't appear to be a problem on documents created locally. Another update to Office 2011 for Mac, mostly Outlook 2011.
This helps a little in my frustration, but the behavior really needs fixed.
I've since changed the blink rate to 200ms via changing the default in Word's plist file. I think that it stays in whichever state it was last in, which 50% of the time is invisible. As I write this post and keep going back to word I'm noticing that it seems erratic as to what behavior it's acting. This makes it painfully difficult to edit text without using the mouse. However, in Word 2011 I'm constantly frustrated because the cursor disappears, or defaults to the invisible state of the flashing sequence, while I'm typing or moving it. It then goes to the flashing sequence once you stop moving it with arrow keys or typing.
The text cursor, or caret, is normally in the visible form in applications at the start of its display cycle.