When playing as a berserker one of the most important things is to keep moving. You definitely aint a tank and your HP is very limited. If you try to face a soldier class face to face you will get your ass handed to you very quickly. You have the advantage against all one handed weapon wielders in circle strafing as your hit cone is larger than theirs. So keep circle strafing around those tanks as long as they cant hit you. If the tank has some skills however he will be able to hit you and at that point you should step back and only step back in when you’ve got a combo charged up to it’s finisher. Unpredictable movement is the key. The tanks white swings will hurt you more than your white swings can hurt them.