Finally we read the words one has wanted to for several chapters;

It would be a great pleasure to know Robert Martin.

Was happy to read these as Emma's thoughts.
But I felt a disappointed when I read;

High in the rank of her most serious and heartfelt felicities, was the reflection that all necessity of concealment from Mr. Knightley would soon be over.

I take this to mean she'll tell Mr Knightley about Harriet and her feelings for him.

Is that necessary? How does it add felicity to their relationship or would to their marriage?

I was quite appreciative of her sentiments back in CH:49;