The first work I have done with the small indexing system ******* was this 60-degree dovetail cutter with TCMT inserts. As I often do in my projects I used my eyes and my experience to make the holes. To find the exact spot where to run the hole, in other videos, I saw using the classic zero reset systems.

But Since:
is the fundamental operation
If I'm wrong for only two tenths I risk of throwing away all the work
it is better to decentralize the hole at at least 0.1 mm from the insert hole

Well, I preferred to stay away, and adjust the measure with both the mill cutter and the experience.
The result was good though I risked to remove too much material, I managed to block the two inserts in the same identical position and so they touch the piece at the same time.