Small grain reseeding is often sporadic, not something that you can always depend on if you want a nice stand growing again. There's many factors coming into play, such as wildlife cleaning up the seed in some areas, germination viability, uneven droppage, moisture availability, and seed to soil contact when it drops. A farmer seeding a crop can control some of these variables. I sometimes have had great reseeding on oats, the next time hardly any. Seeding something at a heavy rate and then mowing is probably your best path to success.