I cut some wheat this summer that was 19-20% and they put it in an aeration bin. As far as I know they didn't have any problems with it. That said... when they know it's going in that wet they don't fill the bin. There's enough bin space there that they can spread that over a few bins, then once it stabilizes, run it back up the leg and dump it in another bin.
From what I understand, 17% is generally the safety line for most grains on air around here. Dry storage is about 13%. This is with small grains. I don't know about corn.... I would think if you were doing any volume a drier would pay you.