To push or not to push

That day i was pushing hands in class with my teacher and he told me something:

When guiding the enemy's hand back using lu(roll back) or peng(ward off), do not guide it too far back or too far out as it opens up an opportunity for an elbow attack directly to the chest or solar plexus!

Just a note, to give balance to my comments on the last post about the loosening shoulders part.

My teacher always says, there are 2 parts to push hands(tuishou). One is technique and the other is kungfu(depth of skill).

Technique is knowing how to place your hands and how to move such that you would not be caught in a disadvantageous position.

Kungfu(depth of skill) is how developed is your listening, sensing and timing skills are.

Technique and kungfu go hand in hand but if you concentrate on one and neglect the other, then you are doing tai chi the wrong way.