@Brett
A lot of projects still have a strong dependency on ORM 3 (e.g. as of Grails 2.3.9 a lot of important plugins only support Hibernate3).
For example, this bug renders the fetch joins expressed as Grails queries unusable (https://jira.grails.org/browse/GRAILS-9829)
It would be very nice if this bug could be fixed in ORM 3 (I believe it works in ORM 4).
I am willing to create a test case if you think it is realistic that this gets fixed (Stian Brattland's example is fairly straightforward)