Mike might be disappointed with this first evaluation run but has a very typical pattern and he is not as far down the rabbit hole as he thinks.
First a few explanations about the evaluation run, the HR level that I use is in a general range of 5-10 beats slower that you would find running at marathon pace. Why? Somewhere in that range is your maximum steady state. While the pace of the evaluation run has some value, it is the ability to maintain a pace at a consistent heart rate that is important at this stage. If we look at Mike's first eval you'll see 6:15 then a 10 second drop, then a 3 second drop, then a 6 second drop. Mike is having a hard time maintaining stability at a given heart rate, his system wants to still cheat by using inefficient pathways. The next ten weeks will have Mike staying away from those inefficient pathways (which can be fully redeveloped in about 7 weeks with the introduction of speed work).
What should you be looking for in eval runs during the base phase? First look for a very small drop off at the heart rate even if the average pace does not change. 6:25, 6:25, 6:25, 6:25 at the same HR would be a positive sign that the steady state pathways are developing. A second sign would be the HR returning to 120 (or what ever HR you pick as your recovery point) more quickly. The least important at this stage is running the evals faster, stability and recovery are the most important.