Personally, I think it is right that you can't appeal.
Forestieri got sent off when he shouldn't have but would people feel the same if he'd got his first yellow for 'diving' when actually fouled and then his second yellow for a mis-timed tackle. He's still only picked up one valid booking.
I think if the yellow card means a sending off then you should be able to appeal it if the decision was a debatable one. Frankly, I want to see 11 v 11 if at all possible and for players to get sent off maybe for two minor transgressions, that is ridiculous.
If I could change a rule it would be that one. Send off for serious foul play, sure. But sin bin for totting up of other offences. When a player gets banned for totting up of yellows it only benefits subsequent opponents rather than teams they were playing at the time. Give them 10, 15, 20 minutes on the sidelines instead. If it stops time wasting, shirt pulling or descent in the game where the offences occur then that would seem fair to me.
