I know exactly what you mean about wishing you didn't know these things sometimes. I mean you barely scratched the surface on the inaccuracies and errors of this episode, as I'm sure you know. They take such liberties.
I actually just watched the most recent ep. last night with my brother (a fourth year dental student), my mom (a pediatrician) and my dad (a dentist) and we all sat there laughing at all the inaccuracies and missteps. I think I might have guffawed when House ordered an MRI because they were thinking neoplasm. As soon as he jumped straight to MRI without a chest x-ray or CT, which are far better for visualizing that sort of thing, I knew the guy had to have the key still in him. But then, I do study in the school where the MRI was invented.
My younger brother, who's still in high school just wondered why we couldn't sit back and enjoy the show. Their complete disregard for medical accuracy is something I've chosen to mostly overlook because the show amuses me, but it definitely irritates me when I know just how many people watch it and think it demonstrates the reality of medicine.
I actually really wanted to write some crack!fic where House and Wilson watched an episode and pointed out and poked fun at all of the medical inaccuracies, but haven't had time yet. This week's episode would make great fodder, but then so would many many others.
Ah well, it is what it is, and at least it's entertaining. :)