Comment 5 for bug 111940

The goal is to ensure that all released and supported pacakges can never reach an unstable state. When a large number of packages is affected, the name change and conflicts may be used (or a false soname bump) to ensure that there is no problem, and that no packages are missed. When a small number of packages is involved, sometimes the migration is handled without such changes. When upgrading to 7.10 from 7.04, updated libhunspell, firefox, and openoffice.org-core packages will all be delivered simultaneously, so that a user of either release should never encounter this situation.

I'm not sure you're mistaken, just that practice is sometimes different than theory. The final solution may well include a change to package names.