Actually I don't agrre with the way the penalty was enforced, My personal opinion is that the offender come in the pits and serve the penalty.
Think about it this way, if Rossi would have come in he would have been in longer than 10s, he would also not be leading when he came back on the track.
He only got done for the 10s, he would also have been done for the time it takes to come in and go out of the pits if he would have to go into the pits to serve his penalty.
TAKE RESPONSIBILTY FOR YOUR OWN ACTIONS