BI Server with TN

Is there a need for BI Repository Server in the run time environment when i dont use process monitor (PM) to monitor my processes that are developed using BI ?.
These processes(conversation scripts) i monitor in my TN conversations.
Apart from the design time information what other runtime data that BI Repo server when the conversation scripts run ? my impression is that all these run time information is stored in TN DB and if i dont use PM, I can live without BI Repo server in run time environment.
any thoughts …

Thanks and regards