The peloton is an amazing thing. It has a chaotic predictability to it, the fact that you're in control of your own bike, yet also absolutely not at the same time. It controls 80% of your movements, and leaves you to play with the other 20%. A sports director's race briefing is centred around being in the right part of the peloton at the right time, and that is almost always the difference between winning and losing.
A rider can be physiologically capable of winning Milan-San Remo, but if they can't enter the bottleneck - the entrance to the Cipressa - placed amongst the top-30 riders without expending too much energy, then I'm going to say that it is an impossible task to actually win that race.
