Okay, so we all know when Harry goes to the cave with Dumbledore and gives him the potion, right? So, Harry uses the spell "Aguamenti" which by the wiki page says the spell blasts out drinkable water from the tip of the wand. Why didn't Harry just put his wand in Dumbledore's mouth and give him water? That whole Inferi situation could have been avoided, so was it just because the writer wanted to put them in a life-threatening situation. Also, couldn't Kreacher have saved Regulus by putting water in his mouth with elf magic?