Great question Mark! It sparked some good conversation within the Q2 team. The only hesitation with saying The Caliper API is due to the network effect you mentioned. However, we don't really like making you recreate all the steps that enrollment endpoint on the API covers for you either (for all the reasons you mentioned).
Use the Caliper API endpoint at this time and perhaps we will begin making a workflow object that could be utilized by both the API and our SDK users without the additional network requirement.