It might be semantics but... you're right in that the TQ limiter MUST be used in association with the OEI training switch and that is the only situation it is REQUIRED by the RFM, but to say or imply that is the ONLY time it can be used (as you did) is misleading. For example it is often used for offshore takeoffs when the required CAT A power is 110% TQ in order to prevent the pilot accidentally pulling past 114% through to 121% and bleeding NR. At least one major EMS/SAR operator requires TQ limiter to be switched on for all operations (it's in their before T/O checks).