Not sure which image or clip you are looking at Allan.

Normally both hands are in front of the body once you are used to the method. It might look like the tiller extension is near the face in some of the video, but wait for the sailor to move or twist the body and it becomes clear that the extension is actually in front of their chest a good foot away from the face. Plus it is the end of the extension that can hurt … not the side.

Have a look at the fleet racing photos – these are high level regattas with world’s best sailors.

All are sailing this way so both hands have freedom of movement to work together to sheet in and sheet out. The key to gaining control in stronger winds. The two hands can only do that if they are in front of the body and the tiller extension can move freely with the hand that is holding it.

The extension under the arm would be too restrictive for the sheeting action of the two hands.

Sorry if I am misunderstanding.