Eg donation and donate have currently been used once each.
If they were to be set up as synonym, it's not clear which would be the "master" tag (if it matters).
Should such cases be left until they've been used more frequently, or should the synonym be created immediately?
It really depends on the tag.
If the master tag would be obvious, say having "Windows 7" and "Windows XP", the master tag would be "Windows", one should either create the synonym immediately.
If the master tag is not obvious, one probably should wait and see which tags are used and which aren't. If a tag is not used more than once over a certain period of time, it is automatically deleted, and then the problem solves itself.
