I've verified Jane's email below. The Camel model AbstractNode defines an "Inherit error handler" check box by default. It appears all of the other palette components define one on their own as well (resulting in two). The simple answer is to just remove the AbstractNode's insertion of this checkbox.

ref:
https://github.com/fusesource/fuseide/blob/7.2.x/plugins/org.fusesource.ide.camel.model/src/org/fusesource/ide/camel/model/AbstractNode.java#L175