Lumped - Capacitance distributed will not consider the effect of xtalk
Coupled - Will consider the effect of xtalk
It wont be sufficient if we analyze the timing using Coupled SPEF in PrimeTime . We have to change the read_parasitics command (add -keep_capacitive_coupling) and when doing report_timing , we need to tell -crosstalk to get the effects of the coupled capacitances.