Do not straighten the arm, save some of your reach for later.
Keep the hand level with the shoulder, if it drops the point will go high.
Control the center-line. It isn’t a real constraint unless his angle is so bad he has no choice but to disengage or run away.
Attack. Don’t raise your hand, don’t chase the blade, just go straight forward when you see him move.
You have slow reflexes, do don’t wait. As soon as he starts the disengage, attack.
Make it a real lunge. Use your full distance to your advantage.
When in the constraint, you are hunched down a bit, ready for the lunge, you are in a good defensive position. You are not standing up straight waiting to get punked in the head.
From tournament on the 21st.
The hand should never be over the knee. It should be to the outside when constraining to the outside, and on the inside when constraining on the inside.
Be subtle, don’t make it too obvious you are making a constraint.
When constraining to the outside, be in 3rd with the hand outside the knee. (See also Fabris notes.)