There are actually ergometers now that can truly simulate climbing. You can actually do all your training on them and not ride outside for months or even years. Yet when you do, it feels like you never stopped riding on the road. No funny business and none of the traditional loss of power transitioning from outdoors to indoors in the fall and then taking another hit in the spring transitioning back to outdoor riding.

Those of you who also live in mountainous areas know that a winter of riding rollers or even a few weeks without climbing will cause you to lose your "climbing legs." That's no longer the case.