Eh, don't get this one, why?
Definitely seen harsh concaving cause problems at the base of the splice on the back which is a modern thing. Also bats being seriously mass produced is a relatively recent thing - wouldn't be surprised if that's a big contributor to the amount of handle/splice problems, along with skinny handles.
Apparently flat faces create more impact vibration on the edges which can run up the blade and create shoulder issues/splits . Rounded edges were always done to allow balls to deflect better at an angle/not bare the full brunt of edge impact . Don't take this as gospel as ive not experienced this myself....ive just heard a few batmakers say this .