Smaller bearings mean lower operating speeds. Higher bearing speeds degrade the oil film that may cause metal to metal contact. Smaller bearings are easier on the oil film.
A big old bearing in a land yacht like a big Olds or Chrysler is likley to never stress the oil to any degree. But repeated 6000 rpm blasts down your favorite back road in your MAY... another reason to use a good oil if you are inclined to hit the go pedal whenever possible.
There's a reason endurance engines like smaller rod bearings (and main bearings)... 1.850 and 1.88 are the norm right now.
