I hit the 3/4 mark in Choice. I lost sight of the ground.
Even though I still think it works better with the scene coming earlier - my sense of panic and not knowing what to do comes from that dreadful 3/4 point more than anything else. Once I got working on it tonight, things started working themselves out, of course.
But there is something about that 3/4 point. And it's not just writers who experience this - I've seen it with painters and people building their own houses or putting together a marketing campaign. I think you're far enough away from where you started that you lose sight of the initial impulse, but you're not far enough along to know it's going to work out just fine. You've lost sight of the shore, but you're not seeing the land across the ocean yet. You have to trust it's out there and keep swimming until you hit it.
So, I guess I'll have to tread water for a few days until everything loosens up and the writing feels comfortable again.