D-pull front derailleur? Dual pull?
 

I've been organizing derailleurs lately and I've come across a bunch that seem that they could be used for both bottom and top pull bikes. Take the following derailleur for example.

http://g01.a.alicdn.com/kf/HTB1otD1J...railleur-b.jpg

Look at where the cable connects on the back. (The "lighter grey" thing.) Now, I believe the socket bolt on the far side swings DOWN, so obviously it could be used with a bottom pull bike. (I'm not sure, I'm looking at an X5 in front of me where as the picture is an X7) However, if you look on the close side you see a cable guide that would allow the same socket bolt to be used with a top pull bike. (If the cable goes through the cable guides then connects to the same bolt.)

Is this the intention of these cable guides? I mean, they certainly WORK that way, and I see no other reason to include them other than to make the derailleur compatible with more bikes.

Can anyone confirm my hypothesis?

I won't speak to that specific FDER, since I'm ignorant about SRAM.
I know Shimano has at least "some" that are both top or bottom pull in their "Mountain" FDER's.
EDIT- It appears MOST of their mountain FDER's are dual pull.

The cable actuated rocker arm has at it's other end a cable routing groove (for when the cable decends from above). Unable to see from this view but likely present is another cable routing groove under the triangular shaped plastic piece which houses the pivot having the chromed "C" clip on it's end. Andy.

Many Shimano MTB derailleurs use the same concept; you either connect the wire directly or wrap it 180 degrees around a drum type of feature and then connect it. The leverage is the same either way since they are made with a common radius.

Great, thanks guys. I just needed verification that dual pull derailleurs actually exist. (I had never known.) They're now organized into their own box at the coop.