Keyword Synonyms don't work

Question

Keyword synonyms do not appear to set up a bidirecional relationship between the keyword and the synonym
Define a keyword and specify a synonym
Tag an image with the keyword (not the synonym); The image will appear under both the keyword and the synonym in the catalog
Tag an image with the synonym;  In this case the image will appear ONLY under the synonym, as if the synonym is now a new top-level keyword
What's the point of the synonym definition if it goes only one way?  You can't use the synonyms interchangeably with the keyword, you have to remember it's a synonym.  This can't be working as designed, can it?

Answer 1

Tag an image with the synonym;  In this case the image will appear ONLY under the synonym, as if the synonym is now a new top-level keyword.
When you enter the name of a synonym into the Keywording > Enter Keywords text box, it actually does create a new tag of the same name and apply it to the image. That new tag has no relationship to the synonym or the synonym's tag.
A related issue is that synonyms can't be searched via the Keyword List > Filter Keywords box; see this thread for more details:
http://forums.adobe.com/thread/663188?tstart=0
It appears that these changes (whether bugs or deliberate design) were introduced in LR 3.