What are the under-the-hood details when it comes to starting a Pipeline like this (just a copy paste example line from the demo code of Pipelines API):

`split_counts = yield SplitCount(entity_kind, property_name, *value_list)`

Will a `yield` just enqueue one (1) task to the task queue, or is Pipelines handling this internally using different amount of tasks for each Pipeline on its "own" according to the job being done?

The context of the question:
Solving the job from scratch keeping full control using a combination of task queues, async url fetches, memcache, backends/modules, hence controlling all specifics about the tasks and the corresponding task queues being used;

or,

just rely on Pipelines.