add this to your player in debug console in editor preview:
player addEventHandler ["Put", {player sidechat str ["PUT", _this]}];
player addEventHandler ["Take", {player sidechat str ["TAKE", _this]}];
Now open Inventory and drag the watch to the ground
PUT event handler is fired
Close inventory, point at the watch until you see "hand" then press Spacebar
Player picks up the watch in puts in in assigned slot but no event handler is fired
Open Inventory and drag the watch to the ground again
PUT event handler is fired
Now drag it back into assigned slot
TAKE event handler is fired