Apparently, it felt smoother than it was. I was with an instructor that day, getting checked out for advanced and once or twice we felt us getting a little slippery, but two other instructors asked about how I did because they said it looked like I was driving right on the edge and could lose it any minute. I never did though
I think going to a narrower tire of the same compound in the rain would be a definite improvement, because you aren't plowing as much water around.