Don't forget that one parm can have multiple targets. For example, you can make an elbow bend control a series of biceps morphs or change the zone and strength of a magnet as it bends. Or you could have a "smile" dial that gives you a smirk from 0 to 0.5, an open smile from 0.5 to 1 and a grin from 1 to 1.5. The intention was definitely to give content creators the ability to create more sophisticated rigs and a tool to deal with those extreme bends. You can now have extra morphs and magnets that only kick in when the knee bend is > 110 degrees. (Actually, you could have done all that and more since ProPack through Python callbacks.) The thing about deltas - they are deltas as in that the values you specify are being added to the target parm's value. The keys themselves are not relative to each other.