Eric has been my coach for many years. In the beginning, I was not a big fan of HR monitors. It took some getting used to. Now, it has become a great tool and gives me information about myself during my runs. It has just been in the last few years that I have begun to appreciate my zone 2 runs.
At first, I didn't pay much attention to them, they were just slow easy runs. I was eager to get through them. Now, I take advantage of them and I am learning more about my running through them. They are a viable part of my training.
Not all runs have to be about pace or distance. During these runs I focus on my form . I go through a mental check list ; how is my posture, am a clenching my fists, are my feet landing underneath me, is my cadence high, what does my breathing pattern sound like.... It is also a good time to practice drinking and fueling, depending on the length of the run. Basically, I use these runs to help me become a more efficient runner.
The longer the run the more focus it takes because as my mind wonders my pace will either pick up or slow down. Having good form in this zone takes practice and patients. I notice that as I get better on these runs, my running as a whole improves.