I kinda agree. A great as he was as Joker, we'd most likely forget about Heath's performance in that movie if it wasn't for his untimely death. Tameem could learn a thing or two from him.
I disagree profusely. I remember Heath Ledger's joker because he was actually something different, something new for the films (the truly psychotic side of Joker. Most movies play on the goofy side that hits Batman with a giant boxing glove on a spring).
Heath Ledger's performance, imo, was great enough to be remembered regardless of his death. I truly believe that if he had lived, he still would have won the oscar and we would still be comparing future Joker's to the likes of both him and Mark Hamil.