Sportsbike abs is a lot more refined and less intrusive. It allows a certain amount of difference, the bit you get when braking hard, and doesn't chime in. The Glees system isn't as clever, it's a basic set up that cannot differentiate between useful hard braking and potentially dangerous lock ups.
There's a reason that front wheel locking is used during machine control tuition, it's a good way to condition yourself to the feel of a wheel locking, learning not to fear it and knowing that the most efficient braking is at the point just before the wheel locks. At this point the last thing you want is some basic abs system cutting in and robbing you of it. It renders all that tuition and experience useless.
