sorry, you are wrong – re the ABP
(sorry)
Both the ABP and the chainstay-pivot allow the brake calliper to be mounted on the seatstay. This is the important bit, because the seatstay moves up and down, while the chainstay rotates around the main pivot. it's this rotation that they both isolate from the brake calliper.
you can't put the calliper on the seatstay when you also have a seatstay-pivot because the calliper would move in respect to the disc – or at least, you could do, but it's a really bad idea.
rocky mountain are selling bikes with what looks like a chainstay-pivot, and it is, but they sidestep the speccy patent because the pivot is above the axle.
there are very few bikes which are 100% active under braking, to achieve it you need a parallelogram design (see Ellsworth), or a 'DOPE' arm (another parallelogram).
you can buy DOPE arms for most bikes from a company called 'brake therapy' – they even make a kit for ellsworth bikes, which wins my award for 'most pointless bike accessory ever'
re: your last sentence, yes. exactly. it's surprising how many bikes out there are basically just a linkage-activated-single-pivot.
Commencal / transition / kona / cove wotsit / that new nukeproof thing / orange blood / yadda yadda yadda.
i'm a geek, i could talk about this for hours.