I'm not referring to driveability problems as tom is, but when you need to put in enough fuel to support over 600 HP you start to see the distribution problems in the siamesed ports, especially with carbs.
So if it effects the fuel at high HP it must have some effect on fuel anytime. A divided port on the street would still support over 250 HP (naturally aspirated) and have all the benefits of a small port. If this is not true the V8 guys should cut out their dividers and small blocks will out flow the big blocks.
