Lateral interactions due to fringe field overlap or "stray" reflections from optical elements in VCSEL array based interconnects are analyzed. Interacting cavity pairs act as coupled oscillators. The cavity that happens to switch on first, determined by the bit sequence between neighbors, acts as a master oscillator that affects the switch on jitter for the next cite. Earlier analytic results for the BER rate are extended to include the influence of the cavity coupling strength on the switch on jitter. Numerical examples, including pre-biasing cases, demonstrate the potential for a large degradation in BER rate at small coupling strengths. Extreme cases result into complete pulse suppression (bit skipping).