There is SO MUCH more to the institution. You need to know each other, in fact you should have the DESIRE to know each other. The desire to ask your spouse 'What is your favourite colour, what is it that you like to do?'. Riddhima is living with her husband yet she has made no effort to see what perfume he uses. What a dead relationship 😕 And they're planning to spend the rest of their lives together when the wife can't even be bothered to take an interest in her husband's wishes . On the other hand, Armaan and Riddhima were always developing, their relationship became stronger as time passed and needless to say if this compatibility test was taken between them then they would pass with flying colours simply because they always knew each other's likes and dislikes because they WANTED to make the effort. It was never a duty to come close emotionally or physically, instead it was something innate which always pulled them towards each other.
For AR, they never needed that legal label, they were always one soul.