There's something on this site that bothers me, just a bit.
Does anyone remember reading the Half Blood prince? When Harry sees Malfoy on The Marauders Map, and follows him into the bathroom, before having a short duel and hitting him with Sectumsempra? Remember the damage it inflicted? Remember how there was "Blood everywhere" and how snape had to use creams, and spells to heal him?
Next bit.
Remember in the Deathly Hallows how one of the Weasley Twins had his ear cut off by Secumsempra? How george was prett out of it, and how they said that because it was dark, dark magic his ear could never be reattached?
See, to me that indicates the Sectumsempra is a dark, powerful spell. So when i see people bit hit by it and simply shrug it off, keep fighting, or just ignore it "Be a man" it sorta ticks me off. At Grimmauld Place i saw someone get hit by Sectumsempra, and heal with Episkey... EPISKEY, for christ's sake...
It's similar to the idiots who would throw around fiendfyre as if it were incendio, it's just not right. If you don't know the full extent of a spell, don't use it. If you see someone else use it and think "There's a break from the norm. I'll use that" Research it, it's quite simple.
And finally, Stupefy. It's a stunner. If you get hit by it, unless you're a Giant, you're stunned, and cannot move, so don't get hit by it if you don't understand...
Basically i'm having a rant about the unrealistic duelling i've seen all this week...