Beauty is in the eye of the beholder and much of ancient coins is a matter for interpretation. Personally a test cut is fine in my opinion if it doesn't obliterate key details. SO on the OP's coin or my Tet the tet cut are in a good place to the left of the portrait and nothing is really lost by having it there. However a test cut through the owls face on an Athens Tet would be a big minus for me since the owls face is key to that type of coin.