Moving Dexerity fields to different schema?

Idea (untested and off head):

You may be able to move it by manipulating the tagged values on the behavior directly.

from import IDublinCore
from plone.supermodel.interfaces import FIELDSETS_KEY
from plone.supermodel.model import Fieldset

custom_fieldset = Fieldset(
    label=_(u'My Custom Set'), 
    fields=['title', 'description']
fieldsets = IDublinCore.getTaggedValue(FIELDSETS_KEY)
# TODO: if title and description are in a fieldset you may need to remove them there.
# here I'am not sure if this is needed:
IDublinCore.setTaggedValue(FIELDSETS_KEY, current)

Please tell me if this works.