Cable adjustment. Road group has adjustment at the deraileur. Mtb group at the lever. He could have used an inline cable adjuster, but chose to tap the deraileur and fit a barrel adjuster in it.
Cheers
@Cranky started
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Cable adjustment.
Road group has adjustment at the deraileur.
Mtb group at the lever.
He could have used an inline cable adjuster, but chose to tap the deraileur and fit a barrel adjuster in it.