yes.
i have actually been accused lately of talking like him and licking my chops too much unconsciously when i dont even realize im doing it (usually after a drink or two

).
i think most are really overdoing the voice. it needs to sound weird and creepy of course but its also very deliberate and measured, with subtle tonal inflections. but its not zany at all.
and yeah of course i can recite all the lines and scar stories and monologues etc. but more importantly (imo) i have adapted his manner of speech to my own voice so i can talk in my joker voice quite naturally. it also helps that i naturally have that "flat midwestern" chicago accent that heath worked so hard to fit into his performance.
after all, i cant just walk around all night repeating lines and growling "why so serious?" can i?
i really want to unnerve people and sell the character completely. i want people who know me to be worried about my mental heath for a day or two (as if they aren't already

.) ya know, introduce a lil' anarchy, upset the natural order and all that.