The truth of this was spelled out when RAA/CASA (I think it was) came up with the idea that the aircraft's engine maintenance log had to be sent in with the annual licence fee. Of the first 70 or so sent in only 3 engines fully complied with the factory service bulletins, maintenance schedules and maintenance procedures.
By that logic, then every Rotax engine owner is keeping on top of, and is well trained in maintenance of their engines? just Jabiru owners who dont care for maintenance.