Feedback Can SSD shaders be explained and documented?

We've had a problem where when the game view is set to Simulator, TMP text as seen from the Scene View becomes blurry. I guess it's a resolution issue.
I found a forum post from a few years back that mentioned that SSD shaders that come with TMP can resolve the issue - and they do! But I've not got a bloody clue what they are, why they work, and what the advantages and disadvantages of them are.
Could someone shed some light, and possibly also add them to the docs?