[James Kuszmaul]

Nothing strikes me as obviously wrong with your code.
However, I do have to ask: How exactly did you arrive at that P gain value? Per section 17.13 of the Talon SRX Software Reference Manual, the P gain is in units of throttle / sensor, where throttle is 0 - 1024 and sensor units are encoder ticks (same units as the 1300 you are seeing). This means that your code should cause the talon to apply a throttle of 1300 * 0.00091054 = 1.18 throttle (out of 1024), and it is not implausible that such a low throttle could get rounded to zero. Have you tried a larger P value, tried including an I or D gain, or tried increasing the error?

Edit: Just as a reminder, if you haven't already, be sure to read the Talon Software Reference Manual. It is quite comprehensive and can generally answer any questions you may have.