YAC is a terrible stat. What advantage does a player who averages a 4 yard catch plus 7 yards of YAC have over a player who averages 12 yards per catch and 0 yards of YAC?
It is terrible if taken with no context, but I already provided the 7.0 YPT number, which shows an extremely low rate of production per target. And this stat is very relevant, as guys like Calvin Johnson and Rob Gronkowski are typically among the league leaders, proving your eyes don't lie. The YAC becomes relevant because it shows that Lloyd is a terrible fit for this scheme, which clearly relies heavily on YAC, unless you are a burner who works the deep zone of the field. In other words, the reason Lloyds yards per target is so atrociously low is because he cannot do anything after he catches the ball.
I'll give you a very relevant example:
In 2010, Deion Branch had 92 targets, 818 yards, and 272 YAC. Breakdown: each target results in an average of 5.93 yards in the air, 2.96 YAC, and 8.89 yards total.
In 2012, Brandon Lloyd had 130 targets, 911 yards, and 180 YAC.
Breakdown: each target results in an average of 5.62 yards in the air, 1.38 YAC, and 7.00 yards total.
Branch 2010: 5.93 yards at point of catch, 2.96 YAC, 8.89 yards total.
Lloyd 2012: 5.62 yards at point of catch, 1.38 YAC, 7.00 yards total.
Branch and Lloyd had very similar roles in the offense, and the yards at point of catch are not that far off. The main difference was Branch's ability to run precise routes (resulting in opening more space) and do something besides fall down.
Again, the yards at point of catch are close, but when you look at the ultimate result, which factors in the Yards after Catch, you have a big difference. At 8.89 yards per target, Branch is a very good WR and should have garnered pro bowl consideration in 2010- that average puts him among very good receivers. At 7.00 yards per target, Lloyd should rightfully be on the bench somewhere. Cut the number in half and tell me the difference between a running back who averages 4.45 yards against a running back who averages 3.5 yards per carry.