This has been discussed before ad nauseum, but since it has been brought up again, here we go.
I have never worked C with a runner at first only, but I don't think it would affect the quality of my pickoff call in the least. I work C with 1st and 3rd, and I haven't blown a pickoff at 1st due to the extra 15 feet. The angle from C does naturally open you up without having to take those forward steps that are required (and hard to do properly) from B. The angle you have in C is the same one you get after stepping forward then pivoting toward the base in B, without the stepping forward part.
It is by far better to call the steal of 2nd from C, IMO. First, the angle to the base is a natural 90 degrees, and you aren't looking up the runner's backside like you are starting in B. Second, you don't have to gauge the catcher's throw or take it over your shoulder, because right handed catchers (99.9% of all catchers) tend to miss to the 1st base side of 2nd base, and often nearly decapitate the BU. I find myself trying to get farther left in order to get the angle I want, which puts me extremely close to the path of the throw. Starting in C opens you up to the play, starting with a drop step with the left foot, then just follow the play into the cut, and voila, perfect position. A simple lean left or right, or a little movement on an off-line throw, and you can see every possible scenario.
And before you ask, I didn't learn all this at the L.C. Combine!
