eh - just do a grep. we got plenty of org.eclipse.gef in base.Ok, I've seen it's extensively used by hibernate.
zest seem to be used by jbosstools-esb.AFAIK, jbosstools-esb is not part of JBoss Tools core, but more of JBoss Tools Integration Stack. So we might be able to remove this from our TP and add it to JBTIS one instead.