Wet train tracks (well, wet smooth steel in general - especially steel plates over road work) are a slipping hazard pretty much REGARDLESS of the tire type, size, or tread you've got. Treadless tires will give you a larger contact patch vs. treaded tires, but they slip on wet steel (and large patches of road paint too) as if it were ice just the same.

Your best bet is, as has been mentioned, to always cross wet tracks perpendicularly and maybe slowly, with no attempt to change direction (i.e. steer) when you're actually on it. Same goes for wet street paint, steel plates, and so forth. Keep the tires you have, says I, and use the lesson that experience fated upon you. ;-)

-Warr