I'm more like the "run every other day and call it wonderful" sort of trainer. I can't think of any excuse beyond youthful exuberance to run 2 days in a row. My body just doesn't like that. On the other hand, I do like the idea of running faster, within reason, and am willing to do such things as the Maffetone heart rate based training, at least, as well as I can without a real HR Monitor. Doing this kind of running, which is mostly LSD, with some hills thrown in for challenges, I've brought my 10 mile and Half times down from more than 9 minute miles to less than 8's. Good enough for me for a year's progress.
Now I'm going into my "trail race" season, and times don't equate so well, but the feeling of strength and trail competence is real important. That's what I will train for more than anything. Well, that, and the general and profound joy of running at all.
Maybe this is kind of blathery, but I hope it contributes a little to the considerations.