The number of applications reviewed by an officer is going to vary, depending on the complexity of the cases. That's always been the way, in all my experience in visa offices.
With very simple cases of e-applications that are straightforward acceptances, one could do 40 or 50 in a day. But if one has complex work permit applications, one might accomplish 15 or 20 in a day. So there is a lot of variation depending on what the workload is.