I just came in because of the stretching thing.

Stretching before exercise is not only not necessary, it's more likely to cause injury than not stretching. Static stretching also limits your muscular force and reduces performance.

Before exercise you want to warm up slowly and do some plyo type stuff. The stretching you really want to do is after the ride, to enhance flexibility and prevent injury. I think it helps me with soreness, the research says otherwise, whatever.