He may be in a zone with a long summer where embryos appear for the third crop which in his experience are still viable after the winter (not the 2nd crop unripe leftovers). He thinks that removing the apical tip will help in faster growth of the embryos that appeared late in the previous year. In most of the Northeast the breba embryos appear in June and I don't think cutting the tips will help significantly in breba progress.
I do cut the tips in spring in some cases where I want branching out for the current year wood for the main crop.
Pinching in summer during active growth period for forcing embryos and fruit growth progress is intended to limit the number of active nodes to concentrate nutrients over fewer nodes (figs and leaves).