it has to be assumed there is an increased risk of catastrophic failure until proved otherwise
I contest this point. What SpaceX is attempting to do is tranform the rocketry model into something more equivalent to the airline model. Various components on aircraft are rated for so many hours of flying, and are inspected at regular intervals. Although rocketry definitely pushes the limits of material science further than aircraft do, I see no reason why it shouldn't be possible to rate certain componentry on a rocket for a number of flights.
It might end up being that a slightly used rocket ends up being more reliable than a brand new, untested one. There's no indication your statement is true.
Onto your actual question. It's simply not worth it - both in terms of cost and performance.
The Falcon fairing is made of Aluminium Honeycomb attached to a carbon fiber laminate with cork. It weighs a few hundred kilograms. The reason it is so light is to maximize the total payload that can be carried to orbit. It would take major structural modifications for the fairing to handle the g-forces associated with a SuperDraco abort scenario (up to 8G, I believe). This would add many tonnes of weight (not to mention complexity and propellant) to the vehicle, and would significantly reduce the marketable payload.
Going even further, if you were to face a late inflight abort (at stage separation, the Falcon 9 first stage is already traveling at approximately 1.8-2.0km/s, and needs to conduct a reentry burn for it to survive), you'd need heatshielding and protection built in. Which adds further mass.
Additionally, it is unlikely that the satellite would be able to handle the stresses associated with a complicated abort scenario. Some satellites are already built such that they can only handle stresses vertically, and require vertical integration on the pad (this is one of the many reasons the USAF is requiring Falcon 9 be stacked vertically for military and reconnaissance flights). If a satellite can't even handle being horizontal, it's unlikely it could handle the G's pulled in an abort.
A far better model, and the one that SpaceX is pursuing, is to simply make the vehicle so reliable you need not worry about failure. That's SpaceX in a nutshell, really: Keep It Simple Stupid.