So... I have two theories on the alleged death this season finale and here they are:
What if Kutner's death shows House the dangers of carrying around guilt? Keeping things carefully hidden and letting them simmer for years? (Kutner's dead parents... House's youth, Amber, Infarction) and he suddenly feels forced to let all of it out because House just doesn't want to die that way?(after years of pain for both of them it's such an easy exit)
Secluded, private, troubled, damaged House letting things out? Hell, that'd break me down! I mean he pushed everything as far away as he could and it just comes rushing back over him? That would break even House!
And... it shows House that it doesn't matter whether he has friends or a lover for as long as he carries this around with him: he could, suddenly decide that it's just too much regardless of his apparent happiness. And that is something he's been extensively searching for this season and all the seasons before this one; what if he, despite decreased pain, a friendship, a lover, still isn't happy just because of his past, his guilt and all his troubles? He's been taught from a very young age that showing emotion is wrong... and now not showing emotion is either stealing his future or... lethal?
He'd be trapped. He would either have to change dramatically and defy everything that has ever been instilled into him or let his own fears drag him down. They did say that they would get deeper into House's psyche, didn't they? Well... House is scared of change, he's scared of showing emotions and mostly in denial about them... so now they are there, they're ugly and present and he just can't take that.
But he does have to communicate these things to people to simply cope.
It's a mental affair, it's not just for the drama, it's reasonably cataclysmic... and in some screwed up way, it's actual progress for House.
Kutner just seems to obvious... it adds up too nicely, like they're tempting us to believe it's Kutner and meanwhile killing off someone else.
The Hindu priest could be patient related... he could be the patient for all we know.
If the event really is contained inside House's head someone commits suicide there and the fallout will be created because House would be mentally unstable and since his brain is the focus of the show the fallout would last well into S6. House sees his brain as the biggest part of him, all there is to him at some times... everybody taking inventory of where they're at? This could do it.
They respect House, love House for his intellect, his wit, his personality... but that's all a carefully constructed façade he's worked on for years. If the loss of all of that doesn't make everyone inspect what they're about, what House is in their lives, what they might have been hiding or denying, then I don't know what will!
House being in New York is also related to the breakdown according to KJ... if the death of a real character inspires the breakdown then what's he in New York for? That does not make sense... I'm thinking narcotics, side affects, introspections.
And Kutner's introspection could inspire the things with his past an such to come out and then he has an arc.
They said he would have an arc, right? But the death thing is just going to happen without warning! How is that an arc? The show has an arc, maybe, but Kutner wouldn't have any because he would be dead at the start of it whereas the exposé of his turbulent past will actually land him an arc... and if they tell us this prior to his suicide, (which would be the most probable course of action if he killed himself) there is no shock.
This is another side of House... the cast being pretty much the same next season? Well... there will be a House... but who says it's the same man as this season? Or any season for that matter. And everyone will be changed by this if it happens like this... same cast, exact same cast actually, but a different version of all of them.
House, as the title of the show predicts, is a constant for everyone: He is a jerk, he will know, he will offer guidance, he will mock you, he will annoy you beyond believe... and that doesn't change. That's the constant, that's what makes House stand out between other TV doctors: brilliance and a slightly toxic yet charming personality. If he loses that for a few episodes...
All will not be well in the world of every single character.
They will revalue everything in their lives and come out a different person because of it: he's a sort of compass to all of them, they see him as stronger, more resilient than any of them and if he's breakable, they are simply doomed.
This would be because of a drug... a dramatic end to House's quest for happiness, no deaths, character development all around...
and maybe, when House comes out of his haze, he will see them there... and the epiphany will help him, help them all, to get back on track.
EDIT: I just thought of something about the next episode that would go along perfectly to the drug related theory. While starting off directly at the patient as seen in the first 2 minutes of "locked in" seems typical for that kind of episode... it also is a perfect excuse to conceal the cause of the crash! House could've gotten a side effect like dizziness or disorientation that caused him to crash the bike but we won't get to see it! And... the crash can be showed in a matter of 10 seconds if someone hits House's bike or something... so it's not that hard. House being in New York is said to be related to the breakdown. So he gets into a drug trial there, has side effects while still adjusting to it and receives the rest of the drugs by package while his mind begins to deteriorate... how does that sound?
That's all I have...