Hey Martin, given the 6 piston front calipers and their larger surface brake pads, that sounds hard to believe. Did you observe this yourself?
We'd actually performed it during MSL a couple of years ago; everyone was curious, the instructors as much as ourselves. To balance the odds we then also swapped the bikes, so then my friend on my non-ABS and me on his ABS-II/CBS... bummer, same result, it suddenly took me (marginally) longer to full stop from 80kph/50mph on the ABS-II then my friend on my non-ABS (we did 5 runs each). Controlled conditions, always performing
max possible braking (the non ABS with mewling tires (rarely reproducible out in the real world...), the ABS-II well in its control range (feels weird when lever and pedal start to pulse...), dry, abrasive tarmac, no traffic, etc...
At the first meters both decelerate rather identically, on the last few meters where the ABS kicks in the non-ABS gets the advantage ... still, the experiment gave a marginal difference, those 1~3 meters will not be there in a real traffic situation... the instructors however saw their expectations confirmed, as its the very same with cars: on dry road nearly/partly locked tires (non ABS) are converting the most energy (heat, abrasion) thus providing the shortest technically possible stopping distance, vs an active ABS 'looses' a bit due the lower friction between tires and road...
Don't try that at home/on open roads, and keep in mind that also on an ABS motorcycle the wheels
can (and will!) lock up on the very last ~1 meter/~3 feet before full stop... (the wheels rotate too slow for ACU there to detect differences...) we observed that more then once, a friend of mine went down heavily with his ST1300 during brake training at an MSL, the front locked up, the steering tilted to the right and down on the deck he was, nasty (suffered a bad knee injury there)... practice a lot (preferable during professionally guided training lessons) and condition yourself to slightly release the braking pressure before the vehicle comes to an halt... ABS is an excellent helper, but its
not foolproof...