AFAIK, there’s different types of ABS and I think only the latest and most expensive works on wheel speed differentials. I think most are just independent wheel speeds and whether the wheel seems to have stopped.
I gather Bosch owns many of the ABS patents, so enforcing ABS does rather prop up German manufacturing.
Wikipedia has an interesting page - http://en.wikipedia.org/wiki/Anti-lock_braking_system
The Insurance Institute for Highway Safety released a study in 2010 that found motorcycles with ABS 37% less likely to be involved in a fatal crash than models without ABS.
I like having ABS for regular roads - in case you “grab a bunch of brake” in a panic - though on irregular roads or off-road its dangerous. I’ve had the bike slide across a bit of light dust and “crash” into another bike … like it has no breaks … in Europe! Its vital to have it “switch off-able”, though manufacturers often make it hard to do so, especially if the bike is running.
http://www.youtube.com/watch?v=OrD65i3FUcU
Oh, it does sound like time to emigrate from Burope.
PS - I’d also hate to do a stoppie on ABS, with the front brake probably juddering as it tries to find grip!