The key to fantastic 270s and sends to the backsides of jumps is to build as much value for taking the backside as you build for taking the jump straight on. With our puppies, we introduce sends to the backside at the same time we introduce taking the jump straight on. The puppy learns to take the jump based on our body position and quickly becomes confident taking the jump from either direction. When we introduced backsides to our older dogs, it was much harder to get the same level of confidence. Our older dogs had a very long reinforcement history of taking the jump from the front and had built the idea that the jump is always taken from the front into their understanding of jumping.
In the video below, you can see my 5 month old puppy showing equal drive for taking the jump straight on, or around the backside and on both sides.