
This is not quite right.  The differential arrival time techinique
requires interplanetary baselines to get good positions.  The
differential arrival at the eight detectors differ by 10's of nanoseconds.
This is smaller than BATSE's microsecond timing capabilities.
BATSE, Ulysses, and Mars Obsverver are used for this technique.

Each BATSE detector does not have a full sky field of view.
The sensitivity of each detector decreases with increasing 
angle of incidence.  The burst position on the sky is determined by
comparing the count rates in different detectors.