We present a parametric study of inter-track interference (ITI) in the context of bit patterned media (BPM) recording channels. Bit error rate (BER) simulation results for optimal bit detection at moderate-to-high signal-to-noise-ratio (SNR) show that, in a certain range of ITI levels, increased ITI does not necessarily degrade performance. This observation applies to channels both with and without intersymbol interference (ISI) as well as in the absence and presence of track misregistration (TMR). In the case of no ISI, an exact analysis of the BER performance of optimal bit detection provides a complete explanation of the observed effect of ITI. For channels with ISI, error event analysis of a joint-track maximum-likelihood sequence detector provides insight into the observed impact of varying levels of ITI on BER performance.