Mixed feelings, mostly in favor.
In favor:
The person requesting must really want it, to ask twice.
If no one else in that swap requested it, no one else in that swap wanted it very much.
We offered the seeds because we wanted them to go to someone who wanted them (and would probably grow them out).
Against:
The person offering the seed might prefer to let two people sample it, even if they waited for another swap to find that person. That's probably why they offered a packet small enough that someone wanted twice as much.
One variation would be to have two end dates for trading. On the first date, people who prefer could "take back" their seeds that had not already been requested and confirmed. But people who wanted to allow double-dibbsing of some of their seeds could leave in any sees they were glad to see swell someones stash.
I know that I have some hybrid seeds that are 5-10 times more expensive than other seeds of the same species. Mainly, I only have SMALL packs of those to split up! I use them and trade them more sparingly, and definitely would NOT want someone requesting 2-3 trade pkts of that rare item so they could direct-sow a longer row.
But when I have plenty of something, I really like your idea. It's easier than having someone email you asking for a bigger packet, then trying to keep records of who-wanted-more-what.
