Originally Posted by
Jeff Neese
Is that like when you're riding in dense fog and can't see the road ahead of you, and all of a sudden you encounter a hill that you didn't know was there? I don't think I'd ride if visibility prevented me from seeing the road ahead. Forget being in the right gear for the upcoming hill - I'd be afraid of running into something.
No, it's like when you're riding up a constant grade for a long time and have your near max effort dialed in and then you reach a section that is suddenly just enough more grade for just a brief time to make you want a lower gear.
Fog isn't involved. Knowing and not knowing that the rise is there isn't involved either. It's just not wanting to do most of the climb in the smaller ring and larger cog and willing to shift into the bigger cog briefly then go back to the smaller cogs after hitting that brief rise. If I'd arrived at that hill in the smaller ring, then I'd stay in the smaller ring. But obviously since we are talking about the large ring, I was coming into the hill with some speed and it'd make little sense to slow down before hand losing all that inertia and shift to the small ring for the climb.
While some try to make this out as what gives less friction, that we know is marginal gains. For those riding their bikes and not competing against and losing to others, it really doesn't matter if they are using a less than perfect combo.