I am not sure what you are asking regarding the rudeness of riding a hybrid bike for a double century. As far as I am concerned you can ride a tricycle. I won't be anymore or any less impressed with your riding prowess either way. My concern would be with me knocking down a 12 hour (in the saddle) double. Frankly, I don't know if I am capable of a double at that pace or not. But then I am 71 years old and only have done century rides. You have not provided enough information regarding the other riders abilities to truly answer the the last question