ezsystems/eztags — comment on commit 100a0a191e40fab493f4e4c80acb28f5a8b15bf4
File: doc/INSTALL line 79
By emodric:

It says it's optional because eZ Find can be optionally enabled or disabled.

If eZ Find is installed and working, you MUST add that field to your schema.xml :)

So, while I agree that the wording is incorrect, it should be say that the step is optional only if eZ Find is disabled :)