This is an issue that Lea and I have talked about a good deal lately. We have great sex together largely because we've had nearly 10 years to train one another. When we first met, we were both more than a little clumsy together. But we asked for what we wanted - we gave and took feedback and, gradually, we trained each other to perform the way that worked best for each of us.
When we play with others, we look for people that that we can play with more than once. We've had a few one-night