I have no issues with 2-Man (2-deep, man-under) in certain game situations. This coverage allows your defensive backs to play in a "trail-man position" (inside leverage, low on the hip) to take away inside breaking routes (slant, dig, etc.) with safety help over the top. Very similar to Tampa 2 (Cover 2) with man coverage principles underneath.
However, the middle of the field is an issue when you can widen the 2-deep safeties off of their landmarks (top of the numbers) and target the deep post (or seam) inside the hash marks. Let's take a look at how the Packers can spread the field and target speed on the post to split the two safeties.
Will we see this route on Sunday up at Lambeau Field? Its possible if the Giants want to play 2-Man vs. the speed and depth of the Packers skill positions. Like I said above, 2-Man is a solid call, but every defense can be beat in the NFL if you get the right matchup.