Tillage demons... thats funny.
Too much tillage is definately a bad thing, like in the 30's when all fields got 2-3 passes every year.
No till farming is good for fields as I have seen an increase in organic matter, but the increased use of chemical that most incorporate in the deal is as bad or worse for other aspects.
Green manure with 1 pass of tillage is awesome, the land has to have enough trash to not blow however. I have some silty soil that I want to plow down this fall, but won't do it unless we get the promised rain later this week.
By leaving the trash till spring, it is dried out and will still help the soil, just not as much as if it was green. 2 reasons, not the same volume of material, and the growth has taken full moisture out to set seeds. The seeds are a further reason to not leave it, they could seed down too much in the way of crop or weeds that are present. Those plants in the spring can take valuable early moisture needed for the next crop.
Lots of guys are going back to summerfallow, but seeding a crop each year and plowing down every other year is etter for the land than a straight fallow.