Two years ago on his American Editor blog, Rich Adin wrote:

Of all the things that are wrong about Word, the text (and graphic) boxes are the absolute worst. Text boxes don’t stick in place; text boxes do not break over pages; if the text box is too big for the page or not big enough to display all of the text it holds, it gives no clue that there is hidden in-box text; text boxes obscure text and other text and graphic boxes — basically, text boxes are evil and not easy to get rid of. Need to box some text? Use a table cell. It works just as well and has none of the evil features of a text box.