I did consider trying to work in the part where they shortened the keys and eventually DES became useless because of it, but it was a bit of a diversion from th

I did consider trying to work in the part where they shortened the keys and eventually DES became useless because of it, but it was a bit of a diversion from the salient (heh) reason I put this on the timeline, that they improved the s-boxes without explanation and that colors any subsequent requests they made to do similar.