His loan at Girona was important because he got to play in a low-pressure environment, and he developed nicely under Michel.
Flick added more depth to his toolbox. Granted, it's not the first time he's played RB and DM this season, he's featured once as an RB under Pep and a few times as DM under Xavi but Flick has done a lot developing Garcia in that regard, especially as a DM.
I'd say he's the new Sergi Roberto in this team for his versatility in a good way. Being able to be called upon to start and come off the bench and do the job is fantastic.