The pistons dipping into pooled oil would not be all that desireable in a running motor.
But as soon as the motor is started, that pooled oil is probably dispersed pretty damn fast, so my guess is that it was intended to be a benefit for initial start-up, when need for lubricaton is most critical. (Just as the felts in Pans served as a reservoir to keep the rockers wet.)
Indian's baffles were different, in that the front was intended to scrape oil windage off of the wheels, and had small holes to aspirate oil upward with the rise of the piston. So basically the baffles shielded the rear and favored the front. Since the windage from the wheels floods the rear, but has diminished by the time it reaches the front, it makes sense.
I do not endorse removal of baffles, unless they are just too badly cracked.
They provide a substantial stiffening effect for the case. Note how H-D substantially beefed up their left cases after baffles were eliminated.
And now back to Cooky's first question about balancing "specs":
The only thing that could be called a useful spec would be the balance factor, which is totally arbitrary. But you will find most folks declaring 60% carved-in-granite for a post-36 Harley Big Twin, whether they understand motor balancing or not.
The Factory undoubtedly chose a lower factor, but only by back-calculating with original rods and pistons, etc., would I guess as to what it was.