Adam what you bought was a drag slick with a DOT tread pattern, I think in fairness to Hoosier they don't expect people to use these thing day to day, they are a dry summers tire.
Andy I only drive this thing once or twice a week from Late April to early Oct. I now they arent the most street friendly things in the world. The few times I drove on them they were fine. they didnt handle all that bad. I know the car isnt set up to take corners fast or run over pot holes.
Im on a very limited budget here so I bought a tire that would work fine on the street for the amount I drive it and wouldnt require me to have a second set of tires for the track.
Regardless of how these tires handle on the street the sidewall should not have dried out 9 months after I bought them. I have Bias ply tires off of a parts car that have been sitting out side for years that dont have any dry rotting on them.