  An OBE potential model for the ^{1}S_0 S = -2 interaction is analyzed with
emphasis on the role of coupling between the Lambda Lambda, N Xi, and Sigma
Sigma channels. Singlet scalar exchange, an approximation to two-pion exchange,
is significant in all channels; surprisingly, the one-pion exchange component
is almost negligible. The size of the channel coupling as a function of the
overall strength of the OBE model potential is examined. Implications of the
analysis for the binding energy of ^{6}_{Lambda Lambda}He are considered; the
new experimental datum may suggest a consistency between the extracted Lambda
Lambda matrix element and the relation implied by SU(3) among OBE baryon-baryon
interactions. \\
