To observers outside the black hole, the gravitational field of a black hole 'escapes' theblack hole not only because portions of the star are still outside the event horizon, but because there is more to the gravitational field than just the part that is produced by matter.

The thing to always keep in mind with relativity is that there are always two different observing frames in any relativistic process. For the black hole, an observer at great distances will see one thing happen, and an observer actually falling into the black hole will see something quite different.

Suppose the person falling in, emitted regular electromagnetic pulses during the whole trip. In her reference frame, nothing strange was happening, except that once she crossed that invisible, mathematical surface called the Event Horizon, she would then be snuffed out of existence within the few milli seconds it takes to fall from there and into the Singularity. Lets say she managed to emit 100 pulses outside the Event Horizon, and 10 pulses inside before she died. What will the outside observer see?

They will count a total of 100 pulses from the infalling observer, however because of relativistic effects, each pulse will reach the distant observer both more and more 'red-shifted' and delayed by longer and longer times. Just outside the Event Horizon, pulses 90 and 91 may arrive as radio-wavelength photons instead of visible-wavelength photons, and the interval of time between these pulses may have lengthened to a week or more instead of a second. The last pair of pulses will be almost infinitely 'redshifted' and not observable, and the time interval might be thousands of years.

This means that when an object collapses to become a black hole, from a distant observer's perspective, the star collapses fast at first then seems to slow down, and fade to black, as the gravitational shifts become significant. Someone riding the surface of this star to its doom would find that the process takes only a few seconds before the star has collapsed inside its own event horizon.

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