I've had 3 trades not go through because of the following "This move would put team XXXXXX 1 player(s) over max roster size.". The player was able to send a trade without designating who to drop. It also allows players who no longer want the trade to go through (and had open bench slots at the time of the trade) to pickup players off of the waiver wire and since their bench is full, the trade is unsuccessful. This is impacting leagues that are worth money.