Here's a poll: How easy is it to obtain fare refunds (vouchers, MCOs, etc.) when the published fare drops?

Any experiences indicating if it's easy, or even possible, for non-U.S. airlines and for pax of U.S. airlines originating outside the U.S.?

Personally, I've tried 3 times (never really thought of it previously but I have been generally satisfied I got the lowest available fares that are sold for the market).

1st time: AS web fare. No refund possible (web fare dropped $10-20)

2nd time: US web fare. Got $74 refund voucher.

3rd time: same as above. Fare dropped any additional $16.