Torrential Rain going to work and coming home.

Coming home was one of those rides were you feel like riding forever, the bike was as smooth as silk and it got me wondering if the bike is faster in the rain.

I ride to work on a Mtb with full tread but it seems to go faster in the rain, I'm sure it has something to do with there being less grip on the wet roads, of course turning is slower and more hazardous but straight line speed is excellent in the wet.

Any thoughts ?