force:recordPreview had a ignoreExistingAction attribute that would force a server trip. I have an issue right now where I have two components:
Comp A - Contains a list of sObjects, saves/updates using custom code.
Comp B - Single component with force:recordData, that will display details from one of the records in the Component A's list.
Right now, if CompA saves a record, and ComponentB had loaded the the record in question at any point, subsequent inits of ComponentB draw from the stale cache.