It may be an artifact of people who have trouble being more likely to write to the list, but it seems that people who have Fedup problems seem to outnumber those who have success outright with no problems first try. That's probably not the case though.
The issues are probably caused by people who add stuff from foreign repos. How else would you end up with an F18 kernel that was newer than the F19 kernel that you were trying to replace it with? That doesn't happen to all F18 users does it? My money is on NO.