I didn't hear any rumors like that other than Gruber's very-late-in-the-game speculation (on the potential resolution, not the yield). If there were any, they were more than outpaced by rumors that the larger iPhone would feature a 1080p (or lower!) resolution.
Here's one from all the way back in October '13 that predicted the 1080p screen on the "5.7 inch" phone:
I think they have made a conscious decision to bet on display scaling technology at high PPI's, so they have the flexibility to always buy the best displays they can get manufactured at the price point they need to hit.
Here's one from all the way back in October '13 that predicted the 1080p screen on the "5.7 inch" phone:
http://www.displaysearchblog.com/2013/10/in-2014-apple-will-...
I think they have made a conscious decision to bet on display scaling technology at high PPI's, so they have the flexibility to always buy the best displays they can get manufactured at the price point they need to hit.