Yes they are underrated. But it's also true if Rani hadn't outnumbered it yet, Juhi has done the most number of films wd him. (Opp him,not opp him, sp appearances including) But from all those films only Darr was an out and out romantic film but SRK wasn't Juhi's love interest. The popularity of the song 'Tu mere samne" over rest of the songs speaks about their romantic chemistry.
I think in Bwood the chemistry between a couple is formed by the success of the film thy do. Every film SRK-Kajol did ws meant to do well hence they got more coverage . From the ones SRK-Juhi did only 1 was a super-hit the rest were averages and flops. Plus the genre of them weren't mainly Romance. Otherwise in my opinion evn in a major flop like One 2 ka 4 they had amazing chemistry in songs like khamoshiyan, sona nahi, Extremely natural, free flowing and u cud actually see the care in intimate scene. If they hug they'll complete it with a squeeze and Shahrukh's peck on her forehead. It will always be that way. There's another song in Ram jaane I found them to have amazing chemistry.If u watch these films, they were meant to fail cs thy were badly made.
In my opinion if Juhi was in DDLJ subsequently go on to do K3G and rest of the movies and they wud be the iconic couple. Juhi was the decent romantic girl next door right at the beginning of her career. She cud've easily pulled off the role. It was later in Juhi's career she discovered her comedy root and the glamour factor. It wud be different but will be good and, I get the feeling wud enhance ShahRukh's character too.
Even in KHKN I found them to be clicking instantly in that last 5 mins than he was wd the actress of the film throughout the entire film.
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