Comment (by Samuel Cupp):

I’ve verified that this fixes the behavior, though actually iterating through all the variables in the pre_groups on every level for every sync is slower than simply commenting out the recursion (~17 time/hr vs ~19 time/hr). I think that we should consider whether this check is necessary or not, and if it is then see if there’s any way to improve the method.

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2653/carpet-presync-triggering-syncs-for-all