Let me explain to the best of my ability stemming from looking at tires in person and also talking to a well versed salesman at a Speed shop. Sorry for the confusion.

I was told, but did not see this for myself that the only tires that M/T makes that are completely DOT approved with no warnings as to "Highway/street" use are their Sportsman Pros. (Sorry I previously mentioned Street Pro-but instead it is their Sportsman Pro).

I have inspected my semi worn and semi aged Hoosier QTP's and they only have DOT on them, nothing else as far as capital letter warnings.
Now with that being said, I have also seen new Hoosier QTP's in catalogs and cars and they now have the "For drag racing only" and or "Not for Highway use"
Just saying, the tires you wear out back and front may be your worst enemies in a argument of legality.

I might just spring for the Coker Pro-tracs for "Highway/Street use" and have either M/T's or Hoosier QTP's on deck on other rims for competition and call it a day.