Explanation on Subscription settings?

Hello @russelltomkins 

In the "Create-Subscriptions.ps1" you set all kind of settings on the Subcsriptions.
Every manual I read says to set the "Event Delivery Optimization" (ConfigurationMode) to 'Minimize latency'. You set it to 'Custom' and set some registry keys.
What I'd like to know is the reasoning behind this. What settings do you set, why, and what are the effects?

Thank you.