Really though? A 6 month announcement-release window? Really?
Japanese developers do it all the time, but only with homegrown releases. For international releases, you probably could use more exposure, but there are plenty of cases; actually, E3 used to be where games were shown in the summer and released in the fall or at Christmas, though that was back in the PS2 days and game cycles have changed a ton. As has been pointed out, Nintendo does it somewhat regularly.
Probably won't happen, but it could work, 18-month hype cycles are not helping games anymore.
("People act like TLG hasn't been worked on for like 8 years.")
...it's not a question of the length of time, it'd a matter of the game's incessant delays.
Not to get too far off on a Last Guardian tangent, but as far as I understand the history, I'm not sure you can say "incessant delays" with the game. It was shown twice in 2009 as a work-in-progress game, shown a third time with a 2011 date, and then not shown again. The herky-jerky ride came from all of the hype threads going into every major trade show (and every year, new comments came about on the development status and Ueda's involvement,) but once it missed its 2011 date and Ico/Shadow Collection came and went with nothing really to take interest in (and no demo, which was rumored... man, that and Mega Man Legends 3, the ones that got away!), there was no more public "delay". It just stopped existing, slipping back into an unfortunate but sadly natural development hell.
