I would not have believed it either, but members here will tell you that a thin saddle that supports only your sitting bones (
Tom Stormcrowe explained this better) will cause less pain like you describe. My old bike had a slightly wider saddle and every year starting was painful -- apparently because the material of the seat rubs the soft tissue causing the pain. I recently got a new bike, with a new thin leather saddle and while I am not pain free, it's never so bad that I can't ride.