Compression and stretch, although a term used widely in Lindy Hop, has been the basis for all my leading and following no-matter what style of dance. I think it helps to think about any dance partnership as a continuing flow between compression and stretch.
What do I mean by these two concepts? Stretch is when each person has their energy travelling away from each other but they are still connected at some point (most typically a hand hold). Stretching away from each other allows you to create stretch or potential energy between you - like pulling a rubber band, so you can then direct your energy in the opposite direction.
Conversely, when the two partners lean together they are both creating a connection by having their energy push together at the same point. You create a physical connection at each end of the spectrum and movement in-between.
Not all styles of dance will use this stretch and compression to a high degree like Lindy Hop, but it's there on a subtle level in all sorts of partner dancing. Once you have a good knowledge of this concept you can throw away the rule-book and start leading and following anything. Finding a balance and response to this feeling is what takes practice. However, it's something you learn by feeling, and the more you tune into it, the finer and finer you can respond to your partner and the more your dance world expands.
By tuning in to making a nice feeling stretch or compress with my partner I start to relax and use my muscles more evenly. I also find that one of my arms is well tuned to this stretch and compression response but the other arm not so much because it doesn't get as much practice. That's why I love a variety of different movements so that different parts of my body can experience connecting, moving and responding.
So if you need a little motivation to shake up your dance moves, see which unused part of your body you can wake-up with varying you dance connections and see what comes of it.