I was thinking something similar. I wonder if the font uses kerning, and you know the rendering engine and the algorithm for how the text was blocked, if you can get exact text back even. Or, at a minimum, rule out words based on the available information. Not a field I am familiar with but I bet there are a lot of ways to uncover the redacted values.
This is the government. The documents are faxed/photo-copied/etc etc. They are a bunch of random docs from random sources and the original creators never thought 'This will be redacted'. They just fired up word and started typing.
