Tom, thanks for your input, I understand where you're coming from, I partially agree, and beg to differ...
Intent Datum Feature!!
This magic new feature is the key, and goes WAY beyond just a reference edge, with the intent feature you can collect and reference all the sketch entities in a sketch feature and replace a "bowling ball" with a "steam iron" and everything will just magically update and follow, irrespective of the number of sketcher entities.
So now for the first time we are able to think in terms of replacing entire sketches with alternate sketches, very powerful.
however I am afraid PTC might have some catching up to do in terms of developing additional automation capability to support this new way of thinking.