As of Lincoln 2012, you can do the brake test on any legal set of tires - dry if it's dry, wet if wet. We used a set that were right at the end of their life. One of the observers looked away at the critical moment and we had to retest. After the second one they were completely shot to sh...aving cream.

1g on dead-cold tires in the dry might be too strict, especially if you run a hard-compound tire. I think a .8g stop in a straight line is enough; that's as good as a passenger car.