The Mercy Rule

[one]

Rather than a team taking off a player would it not be better to allow the losing team to add a player or 2? No one misses any game time then and some subs get more, I’ve used this in preseason friendlies at youth level and it seems to work well.

Works just as good. The problem is in most one sided game, the reason it's one sided is that one team is short of players.