Sounds like more trouble than what its worth.

I agree that what I am proposing is probably not efficient, but otherwise it appears that all
I'll yield will be a lot of green onions. Does anyone know how onion sets are raised and held?

If you can find an old "Joy of Gardening" by Dick Raymond, he devotes a whole page to doing that very thing. Basically he sows seeds mid July, or 4 months before your hard frost. After the frost he pulls them and lets dry. Doesn't wash or take off the tops as they fall off as they dry. He says it is very important to store them in SMALL mesh bags so they can get the air circulation they need to keep. Then stores them in a cool dry place, checking every few weeks and discarding any that have sprouted or rotted.
SOS

Here's an article

Here is a link that might be useful: Growing Onion Sets

Thanks for the great responses. It looks, though, since mine are already in and up that it may be too early for use as sets next spring.

Maybe I'll try any way, or maybe I can find someone who REALLY likes green onions.