The DAPS on a GPS approach give descent steps from the missed approach point, not from the the relevant waypoint activated on the gps unit, therefore requiring the pilot to calculate descent points wrt his current position
I'm not sure how much different it can be, mate, and I've been designing them for a good few years. If AsA is still doing their charts the same way that they were doing 5 or 6 years ago, I've implemented the same thing here. Yes, there's no getting around the need for some quick maths to work out your descent profile - that's just one of many reasons why folks need to do a course of study (of some sort) before going out and learning by trial and error.
I haven't seen any Jepp charts recently but, as far as I recall, they reproduce the chart exactly as they get it from AsA. I'm not trying to say that AsA's charts are better, nor am I trying to defend them, but I've looked at this distance problem for a real long time and not found any better way. Who knows, maybe Jeppesen knows something about it that I don't - that's always a possibility I suppose.