Well, yes, but road bikes do tend to have the smallest contact patches. As such, when I'm expecting extreme nastiness, I generally don't ride my road bike, favoring my hybrid with 37mm tires (at lower pressure).

Also, the main issue (for me) as far as traction isn't the water on the ground - it's the light sand and gravel that the water brings onto the road with it. It's just a little more stable with a longer wheelbase and more rubber on the road.

It's not like I won't ride through a shower if it pops up, but I do exercise a lot more caution, and end up going slower than I would on my hybrid anyway.