This is [still happening](http://meta.stackoverflow.com/questions/132891/visually-subdue-merged-questions#comment368359_132891) and confusing (at least to me, a new mod).

I think the merge function should be streamlined. Currently, there seem to be the following steps (at least for migrated duplicates):

 1. Close the duplicate
 2. Merge it into the main question
 3. <strike>Perform some action that cleans up the stub</strike>

Note that due to the current behavior, you **must not delete the stub**, as this would reject the migration.

It seems as if 1. and 3. could be done automatically by 2.