Haven't done the ZF-6 yet, but here's what I do with the vette (T56):
First gear at the tree, 4500-6500 depending on track condition and tires.
On the third yellow, throttle to the floor and let the clutch out for about 30' keeping RPM up to at least 5000 min. Thumb on top of the shifter, pull back HARD holding pressure.
At an indicated 6800 (about 7100 real life), I stab the clutch to the floor rapidly, and to save the trans, I back the throttle to 1/2 throttle for an instant, which also stops it from banging the limiter. The lever will click into gear in a split second and when done right, the nose will not dip down.
Now I open my hand, palm towards the radio, and PUSH. Do not wrap your hand around it. The springs in the gate will aim it for you. When you stab the clutch again (6900) it will pop into gear.
Turn your hand upside down, thumb towards the floor and pull back hard. When you stab the clutch, it will pop into 4th.
Rinse, repeat.
You cannot "pull" the trans outta gear on a stock transmission. By preloading it with force, and applying the force in a perfect direction (hand position) you will never miss a shift. You do not HAVE to lift the throttle, but I have not found it to be quicker, and the trans will click better if the engine is unloaded and not riding the limiter.