Yeah, the main benefit is to prevent hitting your API so much but it depends on the use case.
If I was approaching this scenario, I'd do everything from the front end (maybe store in local storage to prevent accidental loss of data if you refresh the page) and send everything to the db once done.
I'd maybe have a formula, which takes some inputs like reps, weight, etc., assuming inputs remain consistent and use it as a way to capture a set, as an example. I'd then have a workflow, which would take similar inputs to pass to the formula and then append your set to the array. Do you follow?
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