Chuck, the rudder is offset to facilitate the removal of the driveshaft.

The boat should turn equally in either direction. Many drivers prefer to
turn to Starboard to pick up a fallen skier. (Their view is unobstructed)
With the inboard configuration you can set the desired speed and the
boat will generally maintain that speed whereas many IO's will vary
their speed considerably, especially at wakeboard speeds.
And of course the fins that are mounted on the hull directly below the
ski pylon ensure that the boat will track properly.
There are some fairly decent IO ski boats available, but the serious
skiers should be better served with an inboard.
Good luck and good boating,
Jim

Chuck Gould wrote:
Here's one of the many fields I need to know more about; ski and
wakeboard tow boats.

I'm writing a very short piece (surprise!) noting that a manufacturer
of tow boats has appointed a dealer in the Pacific NW. While looking
over some of their models last week I noticed that they are equipped
with ballast tanks- and I do understand the benefit of making the boat
heacy in the stern to adjust the wake for wakeboarding.

I also noticed that even the smallest boats in this manufacturer's
line (about 20 feet) are all inboards, with the rudder slightly offset
from centerline. I presume the location of the rudder allows the boat
to turn circles in one direction faster than in the other?

I was told that "all tournament quality tow boats are inboards". Is
there something about the function or physics of a tow boat that
precludes using an IO, or is it more of a safety and logistics issue
associated with getting the running gear under the boat away from the
skier or wakeboarder and the tow line?