All snipped, since replying to myself rarely makes sense.

I quote from a few websites...

Q. Does ABS reduce stopping distances?

A. Yes, in braking situations where the wheels on a non-ABS equipped
vehicle would lock up, ABS will generally provide shorter controlled
stopping distance. The amount of improvement in stopping distance
depends on many factors, including the road surface, severity of
braking, initial vehicle speed, etc. On some surfaces, such as gravel
roads, braking distances can be longer, but you will still have the
control benefits of ABS. The important capability of ABS is control. ABS
provides improved vehicle steerability and stability when braking.

(from the General Motors website gm.com, who, presumably, should
understand this concept of ABS)

Rotational-speed sensors continuously monitor each wheel. As soon as
incipient lock-up is detected at a wheel, ABS temporarily reduces the
braking pressureat the wheel in question to such a degree that lock-up
is prevented.

ABS repeats this monitoring and control cycle in rapid succession for
each wheel. This form of electronic wheel-slip control ensures optimum
braking distances while at the same time maintaining full steerability
and stability.

“ABS substantially improves driving stability and usually shortens the
brake path as well,” says Wolfgang Drees, member of the management board
at Robert Bosch GmbH and head of its Chassis Systems division.

(From bosch.de, who designed ABS)


The only data I can find (and I can find no actual study data on any of
this) indicates that ABS when incorrectly used leads to longer stopping
distances (user pumps brakes when ABS is fitted - bad!), and that ABS on
loose surfaces can lead to longer stopping distances.

However, everything I'm reading says that in most situations because it
can keep the car on the limit of skidding more accurately than a driver
(who physically can't pump the brakes 15 times a second, for example) it
will perform at least as well, and even on dry roads where the friction
coefficient is greatest, normally slightly better. On wetter roads, or
differing surfaces, it greatly outperforms the driver with no ABS.

I'm now bored of this and have realised that I've spent a good half an
hour looking stuff up to find out if what I've believed is correct
(which it seems to be) so now I'm off to get on my bike and burn some
more calories, though of course, I'll be making sure to find out if it's
got ABS on before I decide how I should brake in an emergency, of course ;-)

--


Velvet