Yes, but that wasn’t the question! However it further supports the view that you cannot add time to these journeys!
Us mere mortals aren't privy to much more detail than the published estimates of entries and exits, however this is what they tell me:
total season tickets entries and exits at stations from Colchester to Chelmsford including the Braintree branch - 12,400,536
total season tickets entries and exits at stations from Southend Victoria to Billericay - 5,144,140
compared with the total of all entries and exits at Norwich - 4,156,302 (which whilst includes any business and leisure trips to London), also has non London-bound journeys to Ely, Cambridge, Ipswich and coastal destinations. The total entries and exits for season tickets there is just 596,792, i.e. less than 3% of those travelling through Shenfield on GA.
Now as we are talking about two return journeys per day NRW-LST, then that accounts for an absolute maximum of 1600 passengers on four services, for most of whom a 5 minute cut in their jioiurney time (5.5%) is neither here or there.
In practice, high density commuter services are run like a conveyor belt whereas longer distance services (like NRW to LST) are more discrete packages of passengers. If commuter services are needlessly delayed, there is an unstoppable flow that just overflows wherever it can. This is why I likened the GEML to the south MML. Even with minimal delays, there are so many passengers held up that it is ofted impoosible to clear the jam before the end of the peak flow.