It probably won't shorten game time at all. Any time saved by not making a pitching change will be offset by a pitcher afraid to throw strikes to a guy he doesn't feel he can get out, and/or shenanigans teams will apply to get around the rule. And any rule that favors the offense does not cut time out of the game. It's just such a pointlessly dumb rule. i don't even know that game duration is the issue, so much as big gaps of time where nothing horsefeathering happens and you gotta sit there and watch Bruce Bochy or whoever do their interminable waddle to the pitchers mound followed by eighteen meaningless warmup tosses before the same exercise gets repeated in two minutes after the new guy issues a walk it's the worst part of baseball and nobody likes it Some of that stuff is kinda fundamentally part of baseball though..... Nothing horsefeathering happens a lot of the time. Forcing pitchers to face 3 batters, at minimum, I don't see making things all that more aesthetically pleasing (especially if the guy comes in and sucks and you have to sit and watch some guy be wild and struggle or whatever). If a guy sucks, you should be able to pull him out of the game and replace him. Now I agree on the manager waddling, maybe don't have them come to the mound anymore and make the change from the bench by yelling out to the HP you are making a change/calling the pen to send a guy in. There you saved the fans from seeing managers waddle around without making up a new stupid rule.