Well, some people level GLA because they wanna DD with sword. GLA is only sword class, if they say they dont want to tank you can't force them. Also, MRD is a better tank, so why whine about it?
If you die from him not using provoke its your own fault for taking hate, provoke only lasts for 5 seconds and gives extra hate to user for that amount of time.
In other words, your own fault that you died.