I do similar to your process with the over-seeding. But in the last few years we're running into the problem of being unable to raise soybeans to maturity. Bean plots are less than 2 acres in size and the deer mow them off completely once they get 4-6 inches tall. So we've started over-seeding those bean plots in late Aug with radish or winter grains like wheat or rye. To raise soybeans to a full height, I would probably need to fence the plots.