Festival of mud

Last weekend saw the World Cup circus hit a usual stop in Bromont, Quebec, Canada. It poured. The women raced first and it was dry when they started. The winner credits choosing mud tyres as part of the reason for her win - when the rain came she was ready. The men raced later and had to contend with the mud from the start.
It was nice to see a Canuck back on the top step of a World Cup podium, though it was a bloke for the first time. Way to go Geoff.
Like an increasing number of the men, Geoff used a single chainring and a light plastic chain guide. No front derailleur, no shifting problems, and only requiring legs of steel to power up the climbs in the large gear.

Like Formula One racing in the rain, mountain bike races in the mud can alter the results from what is expected. And equipment choices can be more important as the number of people with mechanical problems in this race testifies to.
Good mud tyres have few, large knobs in a skinny package to produce the best traction with the minimum clogging. For the most part, mud tyres are excellent for riding in powder snow too.
If you ever get a chance to ride a mountain bike in fresh powder, it is a blast. The bike slides around unpredictably, but like magic tends to stay upright. Even after leaning over at ridiculous, seemingly impossible angles, and veering off course it stands up and keeps going in the direction intended - eventually. And when you do overcook it and take a face plant, the snow is quite soft and provides a much softer landing than gravel and dirt.

Anyway, for serious racing you have to be prepared for all weather contingencies, which includes heavy mud. Wear glasses, use skinny tyres, perhaps a downtube mud-shield, and if it is pouring with rain you might need some extra warmth in your clothing to make it to the finish with full energy.
In my experience the two worst periods of riding or racing in the rain are as you first get wet and dirty (blech) and then when you have to clean the bike for the next ride. Once you are dirty it is a liberating experience. Eventually, unless you are a pro with your own mechanic, you will be faced with a bike inside a layer of dried muck - a big job. Oh yeah, and riding in the mud is extremely hard on gear. Brake pads, chain, cassette and rings can all be worn out from brand-new in one 2 hour race in the mud. At least the tyres tend to last a long time.