When Pip tells Hebert he loves Estella how does Herbert react & what does his reaction say about him?

When Pip tell Herbert he is in love with Estella, Herbert responded that he already knows. This is an example of Herbert's depth of perception.

Herbert,” said I, laying my hand upon his knee, “I love—I adore—Estella.”

Instead of being transfixed, Herbert replied in an easy matter-of-course way, “Exactly. Well?”

“Well, Herbert? Is that all you say? Well?”

“What next, I mean?” said Herbert. “Of course I know that.”

“How do you know it?” said I.

“How do I know it, Handel? Why, from you.”

“I never told you.”

“Told me! You have never told me when you have got your hair cut, but I have had senses to perceive it. You have always adored her, ever since I have known you. You brought your adoration and your portmanteau here together. Told me! Why, you have always told me all day long. When you told me your own story, you told me plainly that you began adoring her the first time you saw her, when you were very young indeed.”